Publications

@article{WOS:000625792300003,

title = {A conjugated tetracarboxylate anode for stable and sustainable Na-ion 

 batteries},

author = {Kaiqiang Qin and Kathryn Holguin and Motahareh Mohammadiroudbari and Chao Luo},

doi = {10.1039/d0cc08273b},

issn = {1359-7345},

year  = {2021},

date = {2021-03-01},

journal = {CHEMICAL COMMUNICATIONS},

volume = {57},

number = {19},

pages = {2360-2363},

publisher = {ROYAL SOC CHEMISTRY},

address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, 

 ENGLAND},

abstract = {A conjugated tetracarboxylate, 1,2,4,5-benzenetetracarboxylate sodium 

 salt (Na4C10H2O8), was designed and synthesized as an anode material in 

 Na-ion batteries (NIBs). This organic compound shows low redox 

 potentials (similar to 0.65 V), long cycle life (1000 cycles), and fast 

 charging capability (up to 2 A g(-1)), demonstrating a promising organic 

 anode for stable and sustainable NIBs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000665623700001,

title = {Achieving a quantum smart workforce},

author = {Clarice D. Aiello and D. D. Awschalom and Hannes Bernien and Tina Brower and Kenneth R. Brown and Todd A. Brun and Justin R. Caram and Eric Chitambar and Rosa Di Felice and Karina Montilla Edmonds and Michael F. J. Fox and Stephan Haas and Alexander W. Holleitner and Eric R. Hudson and Jeffrey H. Hunt and Robert Joynt and Scott Koziol and M. Larsen and H. J. Lewandowski and Doug T. McClure and Jen Palsberg and Gina Passante and Kristen L. Pudenz and Christopher J. K. Richardson and Jessica L. Rosenberg and R. S. Ross and Mark Saffman and M. Singh and David W. Steuerman and Chad Stark and Jos Thijssen and A. Nick Vamivakas and James D. Whitfield and Benjamin M. Zwickl},

doi = {10.1088/2058-9565/abfa64},

issn = {2058-9565},

year  = {2021},

date = {2021-07-01},

journal = {QUANTUM SCIENCE AND TECHNOLOGY},

volume = {6},

number = {3},

publisher = {IOP PUBLISHING LTD},

address = {TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND},

abstract = {Interest in building dedicated quantum information science and 

 engineering (QISE) education programs has greatly expanded in recent 

 years. These programs are inherently convergent, complex, often resource 

 intensive and likely require collaboration with a broad variety of 

 stakeholders. In order to address this combination of challenges, we 

 have captured ideas from many members in the community. This manuscript 

 not only addresses policy makers and funding agencies (both public and 

 private and from the regional to the international level) but also 

 contains needs identified by industry leaders and discusses the 

 difficulties inherent in creating an inclusive QISE curriculum. We 

 report on the status of eighteen post-secondary education programs in 

 QISE and provide guidance for building new programs. Lastly, we 

 encourage the development of a comprehensive strategic plan for quantum 

 education and workforce development as a means to make the most of the 

 ongoing substantial investments being made in QISE.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000616271200007,

title = {Anomalous gap ratio in anisotropic superconductors: Aluminum under 

 pressure},

author = {Rustem Khasanov and Igor I. Mazin},

doi = {10.1103/PhysRevB.103.L060502},

issn = {2469-9950},

year  = {2021},

date = {2021-02-01},

journal = {PHYSICAL REVIEW B},

volume = {103},

number = {6},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Pressure dependence of the thermodynamic critical field B-c in elemental 

 aluminum was studied by means of the muon-spin rotation-relaxation 

 technique. Pressure enhances the deviation of B-c(T) from parabolic 

 behavior, expected for a typical type-I superconductor, thus suggesting the weakening of the gap ratio  = /k(B)T(c) ( is 

 the average value of the superconducting energy gap, T-c is the 

 transition temperature, and k(B) is the Boltzmann constant). With the 

 pressure increase from 0.0 to similar or equal to 1.6 GPa,  

 decreases almost linearly from 1.73(1) to 1.67(1). Our results imply, 

 therefore, that in elemental aluminum, the gap ratio  is smaller 

 than the weak-coupled BCS prediction alpha(BCS) similar or equal to 

 1.764, and it is even further reduced under pressure.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000627550500003,

title = {Chiral properties of the zero-field spiral state and field-induced 

 magnetic phases of the itinerant kagome metal YMn6Sn6},

author = {Rebecca L. Dally and Jeffrey W. Lynn and Nirmal J. Ghimire and Dina Michel and Peter Siegfried and Igor I. Mazin},

doi = {10.1103/PhysRevB.103.094413},

issn = {2469-9950},

year  = {2021},

date = {2021-03-01},

journal = {PHYSICAL REVIEW B},

volume = {103},

number = {9},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Applying a magnetic field in the hexagonal plane of YMn6Sn6 leads to a 

 complex magnetic phase diagram of commensurate and incommensurate 

 phases, one of which coexists with the topological Hall effect (THE) 

 generated by a unique fluctuation-driven mechanism. Using unpolarized 

 neutron diffraction, we report on the solved magnetic structure for two 

 previously identified, but unknown, commensurate phases. These include a 

 low-temperature, high-field fanlike phase and a room-temperature, 

 low-field canted antiferromagnetic phase. An intermediate incommensurate 

 phase between the fanlike and forced ferromagnetic phases is also 

 identified as the last known phase of the in-plane field-temperature 

 diagram. Additional characterization using synchrotron powder 

 diffraction reveals extremely high-quality, single-phase crystals, which 

 suggests that the presence of two incommensurate magnetic structures 

 throughout much of the phase diagram is an intrinsic property of the 

 system. Interestingly, polarized neutron diffraction shows that the 

 centrosymmetric system hosts preferential chirality in the zero-field 

 double-flat-spiral phase, which, along with the THE, is a topologically 

 nontrivial characteristic.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000611066000078,

title = {Direct-Write of Nanoscale Domains with Tunable Metamagnetic Order in 

 FeRh Thin Films},

author = {Cory D. Cress and Darshana Wickramaratne and Matthew R. Rosenberger and Zachariah Hennighausen and Patrick G. Callahan and Samuel W. LaGasse and Noam Bernstein and Olaf M. Erve and Berend T. Jonker and Syed B. Qadri and Joseph C. Prestigiacomo and Marc Currie and Igor I. Mazin and Steven P. Bennett},

doi = {10.1021/acsami.0c13565},

issn = {1944-8244},

year  = {2021},

date = {2021-01-01},

journal = {ACS APPLIED MATERIALS \& INTERFACES},

volume = {13},

number = {1},

pages = {836-847},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

abstract = {We have directly written nanoscale patterns of magnetic ordering in FeRh 

 films using focused helium-ion beam irradiation. By varying the dose, we 

 pattern arrays with metamagnetic transition temperatures that range from 

 the asgrown film temperature to below room temperature. We employ 

 transmission electron microscopy, X-ray diffraction, and 

 temperature-dependent transport measurements to characterize the 

 as-grown film, and magneto-optic Kerr effect imaging to quantify the He+ 

 irradiation-induced changes to the magnetic order. Moreover, we 

 demonstrate temperature-dependent optical microscopy and conductive 

 atomic force microscopy as indirect probes of the metamagnetic 

 transition that are sensitive to the differences in dielectric 

 properties and electrical conductivity, respectively, of FeRh in the 

 antiferromagnetic (AF) and ferromagnetic (FM) states. Using density 

 functional theory, we quantify strain- and defect-induced changes in 

 spin-flip energy to understand their influence on the metamagnetic 

 transition temperature. This work holds promise for in-plane AF-FM 

 spintronic devices, by reducing the need for multiple patterning steps 

 or different materials, and potentially eliminating interfacial 

 polarization losses due to cross material interfacial spin scattering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000646765400002,

title = {Dynamics of local magnetic moments induced by itinerant Weyl electrons},

author = {Predrag Nikolic},

doi = {10.1103/PhysRevB.103.155151},

issn = {2469-9950},

year  = {2021},

date = {2021-04-01},

journal = {PHYSICAL REVIEW B},

volume = {103},

number = {15},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We derive the effective interactions between local magnetic moments 

 which are mediated by Weyl electrons in magnetic topological semimetals. 

 The resulting spin dynamics is governed by the induced Heisenberg, 

 Kitaev, and Dzyaloshinskii-Moriya (DM) interactions with extended range 

 and oscillatory dependence on the distance between the spins. These 

 interactions are realized in multiple competing channels shaped by the 

 multitude of Weyl nodes in the electron spectrum. Microscopic spins need 

 to be spatially modulated with a channel-dependent wave vector in order 

 to take advantage of the interactions. The DM vector is parallel to the 

 displacement between the two interacting spins, and requires the 

 presence of Weyl electron Fermi surfaces. We also derive the 

 Weyl-induced chiral three-spin interaction in the presence of an 

 external magnetic field. This interaction has an extended range as well, 

 and acts upon the spatially modulated spins in various channels. Its 

 tendency is to produce a skyrmion lattice or a chiral spin liquid which 

 exhibits topological Hall effect. Ultimately, the theory developed here 

 addresses magnetic dynamics in relativistic metals even when chiral 

 magnetism is microscopically precluded. We discuss insights into the 

 ordered state of the magnetic Weyl semimetal NdAlSi.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000658733500020,

title = {Edge channels of broken-symmetry quantum Hall states in graphene 

 visualized by atomic force microscopy},

author = {Sungmin Kim and Johannes Schwenk and Daniel Walkup and Yihang Zeng and Fereshte Ghahari and Son T. Le and Marlou R. Slot and Julian Berwanger and Steven R. Blankenship and Kenji Watanabe and Takashi Taniguchi and Franz J. Giessibl and Nikolai B. Zhitenev and Cory R. Dean and Joseph A. Stroscio},

doi = {10.1038/s41467-021-22886-7},

issn = {2041-1723},

year  = {2021},

date = {2021-05-01},

journal = {NATURE COMMUNICATIONS},

volume = {12},

number = {1},

publisher = {NATURE RESEARCH},

address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY},

abstract = {The quantum Hall (QH) effect, a topologically non-trivial quantum phase, 

 expanded the concept of topological order in physics bringing into focus 

 the intimate relation between the ``bulk'' topology and the edge 

 states. The QH effect in graphene is distinguished by its four-fold 

 degenerate zero energy Landau level (zLL), where the symmetry is broken 

 by electron interactions on top of lattice-scale potentials. However, 

 the broken-symmetry edge states have eluded spatial measurements. In 

 this article, we spatially map the quantum Hall broken-symmetry edge states comprising the graphene zLL at integer filling factors of nu =0,1 

 across the quantum Hall edge boundary using high-resolution atomic force 

 microscopy (AFM) and show a gapped ground state proceeding from the bulk 

 through to the QH edge boundary. Measurements of the chemical potential 

 resolve the energies of the four-fold degenerate zLL as a function of 

 magnetic field and show the interplay of the moire superlattice 

 potential of the graphene/boron nitride system and spin/valley 

 symmetry-breaking effects in large magnetic fields.The broken-symmetry 

 edge states that are the hallmark of the quantum Hall effect in graphene 

 have eluded spatial measurements. Here, the authors spatially map the 

 quantum Hall broken-symmetry edge states using atomic force microscopy 

 and show a gapped ground state proceeding from the bulk through to the 

 quantum Hall edge boundary.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000617431500041,

title = {Families of asymmetrically functionalized germanene films as promising 

 quantum spin Hall insulators},

author = {Lawrence Shi and Qiliang Li},

doi = {10.1039/d0cp06231f},

issn = {1463-9076},

year  = {2021},

date = {2021-02-01},

journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},

volume = {23},

number = {5},

pages = {3595-3605},

publisher = {ROYAL SOC CHEMISTRY},

address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, 

 ENGLAND},

abstract = {Topological insulators (TIs), exhibiting the quantum spin Hall (QSH) 

 effect, are promising for developing dissipationless transport devices 

 that can be realized under a wide range of temperatures. The search for 

 new two-dimensional (2D) TIs is essential for TIs to be utilized at 

 room-temperature, with applications in optoelectronics, spintronics, and 

 magnetic sensors. In this work, we used first-principles calculations to 

 investigate the geometric, electronic, and topological properties of GeX and GeMX (M = C, N, P, As; X = H, F, Cl, Br, I, O, S, Se, Te). In 26 of 

 these materials, the QSH effect is demonstrated by a spin-orbit coupling 

 (SOC) induced large band gap and a band inversion at the Gamma point, 

 similar to the case of an HgTe quantum well. In addition, engineering 

 the intra-layer strain of certain GeMX species can transform them from a 

 regular insulator into a 2D TI. This work demonstrates that asymmetrical 

 chemical functionalization is a promising method to induce the QSH 

 effect in 2D hexagonal materials, paving the way for practical 

 application of TIs in electronics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000646763400003,

title = {High-throughput search for magnetic topological materials using 

 spin-orbit spillage, machine learning, and experiments},

author = {Kamal Choudhary and Kevin F. Garrity and Nirmal J. Ghimire and Naween Anand and Francesca Tavazza},

doi = {10.1103/PhysRevB.103.155131},

issn = {2469-9950},

year  = {2021},

date = {2021-04-01},

journal = {PHYSICAL REVIEW B},

volume = {103},

number = {15},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Magnetic topological insulators and semimetals have a variety of 

 properties that make them attractive for applications, including 

 spintronics and quantum computation, but very few high-quality candidate 

 materials are known. In this paper, we use systematic high-throughput 

 density functional theory calculations to identify magnetic topological 

 materials from the approximate to 4000 three-dimensional materials in 

 the JARVIS-DFT database. First, we screen materials with net magnetic 

 moment >0.5 mu B and spin-orbit spillage (SOS) >0.25, resulting in 25 

 insulating and 564 metallic candidates. The SOS acts as a signature of 

 spin-orbit-induced band-inversion. Then we carry out calculations of 

 Wannier charge centers, Chern numbers, anomalous Hall conductivities, 

 surface band structures, and Fermi surfaces to determine interesting 

 topological characteristics of the screened compounds. We also train 

 machine learning models for predicting the spillages, band gaps, and 

 magnetic moments of new compounds, to further accelerate the screening 

 process. We experimentally synthesize and characterize a few candidate 

 materials to support our theoretical predictions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000582373900046,

title = {Hole doping induced half-metallic itinerant ferromagnetism and giant 

 magnetoresistance in CrI3 monolayer},

author = {Sheng Yu and Yu Wang and Yuzhen Song and Lei Xia and Xiaolong Yang and Hui Fang and Qiliang Li and Xiaoguang Li},

doi = {10.1016/j.apsusc.2020.147693},

issn = {0169-4332},

year  = {2021},

date = {2021-01-01},

journal = {APPLIED SURFACE SCIENCE},

volume = {535},

publisher = {ELSEVIER},

address = {RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS},

abstract = {The exploit of magnetic devices with high magnetoresistance is vital for 

 the development of magnetic sensing and data storage technologies. Here, 

 using density functional calculations combined with Monte Carlo 

 simulations, we explore the magnetic properties and spin-dependent 

 transport of CrI3 monolayer under an electrostatic hole doping. 

 Extraordinarily, the magnetoresistance can be controlled over 10(6)% 

 within a certain doping density range. The hole doping can render CrI3 

 monolayer half-metallic and nearly 100% spin-polarization at Fermi 

 energy level can be achieved. Moreover, the hole doping can 

 significantly enhance the stability of itinerant ferromagnetism. The 

 Heisenberg exchange parameters can be significantly improved and 

 meanwhile, the Curie temperature can be boosted to room temperature via 

 a doping density of 8.49 x 10(14) cm(-2). This study reveals that the 

 carrier doping engineering can enable two-dimensional CrI3 as a 

 remarkable material for developing practical and high-performance 

 spintronic nanodevices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000633580100001,

title = {Isotropic Nature of the Metallic Kagome Ferromagnet Fe3Sn2 at High 

 Temperatures},

author = {Rebecca L. Dally and Daniel Phelan and Nicholas Bishop and Nirmal J. Ghimire and Jeffrey W. Lynn},

doi = {10.3390/cryst11030307},

issn = {2073-4352},

year  = {2021},

date = {2021-03-01},

journal = {CRYSTALS},

volume = {11},

number = {3},

publisher = {MDPI},

address = {ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND},

abstract = {Anisotropy and competing exchange interactions have emerged as two 

 central ingredients needed for centrosymmetric materials to exhibit 

 topological spin textures. Fe3Sn2 is thought to have these ingredients 

 as well, as it has recently been discovered to host room temperature 

 skyrmionic bubbles with an accompanying topological Hall effect. We 

 present small-angle inelastic neutron scattering measurements that 

 unambiguously show that Fe3Sn2 is an isotropic ferromagnet below T-C 

 approximate to 660 K to at least 480 K-the lower temperature threshold 

 of our experimental configuration. Fe3Sn2 is known to have competing 

 magnetic exchange interactions, correlated electron behavior, weak 

 magnetocrystalline anisotropy, and lattice (spatial) anisotropy; all of 

 these features are thought to play a role in stabilizing skyrmions in 

 centrosymmetric systems. Our results reveal that at the elevated 

 temperatures measured, there is an absence of significant 

 magnetocrystalline anisotropy and that the system behaves as a nearly 

 ideal isotropic exchange interaction ferromagnet, with a spin stiffness D(T = 480 K) = 168 meV angstrom(2), which extrapolates to a ground state spin stiffness D(T = 0 K) = 231 meV angstrom(2).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000613720100025,

title = {Laser Scribing of Fluorinated Polyimide Films to Generate Microporous 

 Structures for High-Performance Micro-supercapacitor Electrodes},

author = {Minsu Kim and Min Guk Gu and Heeyoung Jeong and Eunseok Song and Jun Woo Jeon and Kang-Moo Huh and Pilgyu Kang and Sung-Kon Kim and Byoung Gak Kim},

doi = {10.1021/acsaem.0c02096},

issn = {2574-0962},

year  = {2021},

date = {2021-01-01},

journal = {ACS APPLIED ENERGY MATERIALS},

volume = {4},

number = {1},

pages = {208-214},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

abstract = {Laser-induced graphene (LIG) typically exhibits a mesostructure with a 

 small specific surface area, which is detrimental to the electrochemical 

 performance of micro-super-capacitors (MSCs). Herein, 3D nanostructured 

 LIGs patterned on fluorinated polyimides (fPfs) via a laser photothermal 

 method are reported. During laser-induced graphitization, a highly 

 microporous structure in the LIG develops. Consequently, the patterned 

 LIG (LIG-fPI) exhibits a very large specific surface area (1126.0 m(2) , 

 g(-1)) , thereby enhancing its electrochemical performance. 

 Specifically, in an H2SO4 aqueous electrolyte, the micropatterned 

 electrode exhibits an exceptional areal capacitance of 110 mF cm(-2) 

 (determined by cyclic voltammetry), which is 27 times higher than that 

 of a LIG based on commercial polyimides and at least 7 times higher than 

 that of current state-of-the-art MSCs. Furthermore, mechanically stable 

 and flexible LIG-fPI-MSCs with an organic gel polymer electrolyte (working potential = similar to 3 V) show very high power and energy 

 densities of 0.58 mW cm(-2) and 0.01 mW h cm(-2), respectively. Thus, 

 these LIGs are promising for application in high-performance MSCs for 

 flexible microelectronics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000661189100003,

title = {Magnetic and electronic ordering phenomena in the Ru2O6-layer honeycomb 

 lattice compound AgRuO3},

author = {Walter Schnelle and Beluvalli E. Prasad and Claudia Felser and Martin Jansen and Evgenia V. Komleva and Sergey V. Streltsov and Igor I. Mazin and Dmitry Khalyavin and Pascal Manuel and Sukanya Pal and D. V. S. Muthu and A. K. Sood and Ekaterina S. Klyushina and Bella Lake and Jean-Christophe Orain and Hubertus Luetkens},

doi = {10.1103/PhysRevB.103.214413},

issn = {2469-9950},

year  = {2021},

date = {2021-06-01},

journal = {PHYSICAL REVIEW B},

volume = {103},

number = {21},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {The silver ruthenium oxide AgRuO3 consists of honeycomb Ru25+O62- layers 

 and can be considered an analogue of SrRu2O6 with a different 

 intercalation. We present measurements of magnetic susceptibility and 

 specific heat on AgRuO3 single crystals, which reveal a sharp 

 antiferromagnetic transition at 342(3) K. The electrical transport in 

 single crystals of AgRuO3 is determined by a combination of activated 

 conduction over an intrinsic semiconducting gap of approximate to 100 

 meV and carriers trapped and thermally released from defects. From 

 powder neutron diffraction data a Neel-type antiferromagnetic structure 

 with the Ru moments along the c axis is derived. Raman spectroscopy on 

 AgRuO3 single crystals and muon spin rotation spectroscopy on powder 

 samples indicate a further weak phase transition or a crossover in the 

 temperature range 125-200 K. The transition does not show up in the 

 magnetic susceptibility, and its origin is argued to be related to 

 defects but cannot be fully clarified. The experimental findings are 

 complemented by density-functional-theory-based electronic structure 

 calculations. It is found that themagnetism in AgRuO3 is similar to that 

 in SrRu2O6, however, with stronger intralayer and weaker interlayer 

 magnetic exchange interactions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000652839100003,

title = {Magnetization Process of Atacamite: A Case of Weakly Coupled S=1/2 

 Sawtooth Chains},

author = {L. Heinze and H. O. Jeschke and I. I. Mazin and A. Metavitsiadis and M. Reehuis and R. Feyerherm and J. U. Hoffmann and M. Bartkowiak and O. Prokhnenko and A. U. B. Wolter and X. Ding and V. S. Zapf and C. Corvalan Moya and F. Weickert and M. Jaime and K. C. Rule and D. Menzel and R. Valenti and W. Brenig and S. Suellow},

doi = {10.1103/PhysRevLett.126.207201},

issn = {0031-9007},

year  = {2021},

date = {2021-05-01},

journal = {PHYSICAL REVIEW LETTERS},

volume = {126},

number = {20},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We present a combined experimental and theoretical study of the mineral 

 atacamite Cu2Cl(OH)(3). Density-functional theory yields a Hamiltonian 

 describing anisotropic sawtooth chains with weak 3D connections. 

 Experimentally, we fully characterize the antiferromagnetically ordered 

 state. Magnetic order shows a complex evolution with the magnetic field, 

 while, starting at 31.5 T, we observe a plateaulike magnetization at 

 about M-sat/2. Based on complementary theoretical approaches, we show 

 that the latter is unrelated to the known magnetization plateau of a 

 sawtooth chain. Instead, we provide evidence that the magnetization 

 process in atacamite is a field-driven canting of a 3D network of weakly 

 coupled sawtooth chains that form giant moments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000582675600041,

title = {Simultaneously enhanced energy storage density and efficiency in novel 

 BiFeO3-based lead-free ceramic capacitors},

author = {Qianjie Li and Shuaishuai Ji and Dongdong Wang and Jiangyuan Zhu and Leiyu Li and Wei Wang and Min Zeng and Zhipeng Hou and Xingsen Gao and Xubing Lu and Qiliang Li and Jun-Ming Liu},

doi = {10.1016/j.eurceramsoc.2020.08.032},

issn = {0955-2219},

year  = {2021},

date = {2021-01-01},

journal = {JOURNAL OF THE EUROPEAN CERAMIC SOCIETY},

volume = {41},

number = {1},

pages = {387-393},

publisher = {ELSEVIER SCI LTD},

address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND},

abstract = {In this work, a series of novel lead-free 

 (1-x)Bi0.83Sm0.17Fe0.95Sc0.05O3-x(0.85BaTiO(3)-0.15Bi(Mg0.5Zr0.5)O-3) [(1-x)BSFS-x(BT-BMZ)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000577200200001,

title = {Spin reorientation in antiferromagnetic Dy(2)FeCoO(6)double perovskite},

author = {G. R. Haripriya and T. W. Heitmann and D. K. Yadav and G. C. Kaphle and Madhav Prasad Ghimire and R. Pradheesh and J. Joshi and P. Vora and K. Sethupathi and V Sankaranarayanan and H. S. Nair},

doi = {10.1088/1361-648X/abaeaa},

issn = {0953-8984},

year  = {2021},

date = {2021-01-01},

journal = {JOURNAL OF PHYSICS-CONDENSED MATTER},

volume = {33},

number = {2},

publisher = {IOP PUBLISHING LTD},

address = {TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND},

abstract = {We explored the electronic and magnetic properties of the lanthanide 

 double perovskite Dy(2)FeCoO(6)by combining magnetization, Raman and 

 Mossbauer spectroscopy and neutron diffraction along with density 

 functional theory (DFT) calculations. Our magnetization measurements 

 revealed two magnetic phase transitions in Dy2FeCoO6. First, a paramagnetic to antiferromagnetic transition atT(N)= 248 K and subsequently, a spin reorientation transition atT(SR)= 86 K. In 

 addition, a field-induced magnetic phase transition with a critical 

 field ofH(c)approximate to 20 kOe is seen at 2 K. Neutron diffraction 

 data suggested cation-disordered orthorhombic structure for 

 Dy(2)FeCoO(6)inPnmaspace group which is supported by Raman scattering 

 results. The magnetic structures ascertained through representational 

 analysis indicate that atT(N), a paramagnetic state is transformed to 

 Gamma(5)(Cx,Fy,Az) antiferromagnetic structure while, atT(SR), Fe/Co 

 moments undergo a spin reorientation to Gamma(3)(Gx,Ay,Fz). The refined 

 magnetic moment of (Fe/Co) is 1.47(4)mu(B)at 7 K. The antiferromagnetic 

 structure found experimentally is supported through the DFT calculations 

 which predict an insulating electronic state in Dy2FeCoO6.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000613575900001,

title = {Strain-resilient electrical functionality in thin-film metal electrodes 

 using two-dimensional interlayers},

author = {Chullhee Cho and Pilgyu Kang and Amir Taqieddin and Yuhang Jing and Keong Yong and Jin Myung Kim and Md Farhadul Haque and Narayana R. Aluru and SungWoo Nam},

doi = {10.1038/s41928-021-00538-4, Early Access Date = FEB 2021},

issn = {2520-1131},

year  = {2021},

date = {2021-02-01},

journal = {NATURE ELECTRONICS},

volume = {4},

number = {2},

pages = {126-133},

publisher = {NATURE RESEARCH},

address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY},

abstract = {Flexible electrodes that allow electrical conductance to be maintained 

 during mechanical deformation are required for the development of 

 wearable electronics. However, flexible electrodes based on metal thin 

 films on elastomeric substrates can suffer from complete and unexpected 

 electrical disconnection after the onset of mechanical fracture across 

 the metal. Here we show that the strain-resilient electrical performance 

 of thin-film metal electrodes under multimodal deformation can be 

 enhanced by using a two-dimensional interlayer. Insertion of atomically 

 thin interlayers-graphene, molybdenum disulfide or hexagonal boron 

 nitride-induces continuous in-plane crack deflection in thin-film metal 

 electrodes. This leads to unique electrical characteristics (termed 

 electrical ductility) in which electrical resistance gradually increases 

 with strain, creating extended regions of stable resistance. Our 

 two-dimensional interlayer electrodes can maintain a low electrical 

 resistance beyond a strain at which conventional metal electrodes would 

 completely disconnect. We use the approach to create a flexible 

 electroluminescent light-emitting device with an augmented 

 strain-resilient electrical functionality and an early damage diagnosis 

 capability. 

 Insertion of an atomically thin interlayer, such as graphene, between a 

 metal thin film and a substrate can be used to create flexible 

 electrodes with electrical performance that changes only gradually with 

 strain and is resistant to abrupt mechanical failure.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000615795700001,

title = {Strategies in Structure and Electrolyte Design for High-Performance 

 Lithium Metal Batteries},

author = {Kaiqiang Qin and Kathryn Holguin and Motahareh Mohammadiroudbari and Jinghao Huang and Eric Young Sam Kim and Rosemary Hall and Chao Luo},

doi = {10.1002/adfm.202009694},

issn = {1616-301X},

year  = {2021},

date = {2021-04-01},

journal = {ADVANCED FUNCTIONAL MATERIALS},

volume = {31},

number = {15},

publisher = {WILEY-V C H VERLAG GMBH},

address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY},

abstract = {Lithium metal is the ``holy grail'' anode for next-generation 

 high-energy rechargeable batteries due to its high capacity and lowest 

 redox potential among all reported anodes. However, the practical 

 application of lithium metal batteries (LMBs) is hindered by safety 

 concerns arising from uncontrollable Li dendrite growth and infinite 

 volume change during the lithium plating and stripping process. The 

 formation of stable solid electrolyte interphase (SEI) and the 

 construction of robust 3D porous current collectors are effective 

 approaches to overcoming the challenges of Li metal anode and promoting 

 the practical application of LMBs. In this review, four strategies in 

 structure and electrolyte design for high-performance Li metal anode, 

 including surface coating, porous current collector, liquid electrolyte, 

 and solid-state electrolyte are summarized. The challenges, 

 opportunities, perspectives on future directions, and outlook for 

 practical applications of Li metal anode, are also discussed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000550071000001,

title = {Achieving mu eV tunneling resolution in an in-operando scanning 

 tunneling microscopy, atomic force microscopy, and magnetotransport 

 system for quantum materials research},

author = {Johannes Schwenk and Sungmin Kim and Julian Berwanger and Fereshte Ghahari and Daniel Walkup and Marlou R. Slot and Son T. Le and William G. Cullen and Steven R. Blankenship and Sasa Vranjkovic and Hans J. Hug and Young Kuk and Franz J. Giessibl and Joseph A. Stroscio},

doi = {10.1063/5.0005320},

issn = {0034-6748},

year  = {2020},

date = {2020-07-01},

journal = {REVIEW OF SCIENTIFIC INSTRUMENTS},

volume = {91},

number = {7},

publisher = {AMER INST PHYSICS},

address = {1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA},

abstract = {Research in new quantum materials requires multi-mode measurements 

 spanning length scales, correlations of atomic-scale variables with a 

 macroscopic function, and spectroscopic energy resolution obtainable 

 only at millikelvin temperatures, typically in a dilution refrigerator. 

 In this article, we describe a multi-mode instrument achieving a mu eV 

 tunneling resolution with in-operando measurement capabilities of 

 scanning tunneling microscopy, atomic force microscopy, and 

 magnetotransport inside a dilution refrigerator operating at 10 mK. We 

 describe the system in detail including a new scanning probe microscope 

 module design and sample and tip transport systems, along with wiring, 

 radio-frequency filtering, and electronics. Extensive benchmarking 

 measurements were performed using 

 superconductor-insulator-superconductor tunnel junctions, with Josephson 

 tunneling as a noise metering detector. After extensive testing and 

 optimization, we have achieved less than 8 mu eV instrument resolving 

 capability for tunneling spectroscopy, which is 5-10 times better than 

 previous instrument reports and comparable to the quantum and thermal 

 limits set by the operating temperature at 10 mK.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000518412200013,

title = {Adaptive Semantic Segmentation for Unmanned Surface Vehicle Navigation},

author = {Wenqiang Zhan and Changshi Xiao and Yuanqiao Wen and Chunhui Zhou and Haiwen Yuan and Supu Xiu and Xiong Zou and Cheng Xie and Qiliang Li},

doi = {10.3390/electronics9020213},

year  = {2020},

date = {2020-02-01},

journal = {ELECTRONICS},

volume = {9},

number = {2},

publisher = {MDPI},

address = {ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND},

abstract = {The intelligentization of unmanned surface vehicles (USVs) has recently 

 attracted intensive interest. Visual perception of the water scenes is 

 critical for the autonomous navigation of USVs. In this paper, an 

 adaptive semantic segmentation method is proposed to recognize the water 

 scenes. A semantic segmentation network model is designed to classify 

 each pixel of an image into water, land or sky. The segmentation result 

 is refined by the conditional random field (CRF) method. It is further 

 improved accordingly by referring to the superpixel map. A weight map is 

 generated based on the prediction confidence. The network trains itself 

 with the refined pseudo label and the weight map. A set of experiments 

 were designed to evaluate the proposed method. The experimental results 

 show that the proposed method exhibits excellent performance with 

 few-shot learning and is quite adaptable to a new environment, very 

 efficient for limited manual labeled data utilization.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000536902200005,

title = {Chemical vapor transport synthesis, characterization and compositional 

 tuning of ZrSxSe2-x for optoelectronic applications},

author = {Joshua J. Fox and Saiphaneendra Bachu and Randal L. Cavalero and Robert M. Lavelle and Sean M. Oliver and Sam Yee and Patrick M. Vora and Nasim Alem and David W. Snyder},

doi = {10.1016/j.jcrysgro.2020.125609},

issn = {0022-0248},

year  = {2020},

date = {2020-07-01},

journal = {JOURNAL OF CRYSTAL GROWTH},

volume = {542},

publisher = {ELSEVIER},

address = {RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS},

abstract = {ZrS2, ZrSe2 and mixed alloy ZrSxSe2-x materials were achieved through 

 chemical vapor transport. The incongruent melting system of Zr-S-Se 

 formed crystalline layered flakes as a transport product that grew up to 

 2 cm in lateral size with cm-scale flakes consistently obtained for the 

 entire compositional range exhibiting visible hexagonal features. Bulk flakes of the series ZrSxSe2-x (x = 0, 0.15, 0.3, 0.6, 1.05, 1.14, 1.51, 

 1.8 and 2) were analyzed through Raman spectroscopy revealing 

 significant convolution of primary bonding modes and shifting of Raman 

 features as a function of increasing sulfur composition. Additionally, 

 activation of new modes not present in the pure compounds are observed 

 as effects which result from disorder introduced into the crystal due to 

 the random mixing of S-Se in the alloying process. Further structural 

 characterization was performed via x-ray diffraction (XRD) on the 

 layered flakes to evaluate the progression of layer spacing function of 

 alloy composition which was found to range between 6.24 angstrom for 

 ZrSe2 and 5.85 angstrom for ZrS2. Estimation of the compositional ratios 

 of the alloy flakes through energy dispersive spectroscopy (EDS) 

 large-area mapping verified the relation of the targeted source 

 stoichiometry represented in the layered flakes. Atomic-resolution high 

 angle annular dark field (HAADF)-scanning transmission electron 

 microscopy (STEM) imaging was performed on the representative Zr 

 (S0.5Se0.5)(2) alloy to validate the 1T atomic structure and observe the 

 arrangement of the chalcogenide columns stacks. Additionally, selected 

 area diffraction pattern generated from the [0 0 0 1] zone axis 

 revealed the in-plane lattice parameter to be approximately 3.715 

 angstrom.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000599905500047,

title = {Competing magnetic phases and fluctuation-driven scalar spin chirality 

 in the kagome metal YMn6Sn6},

author = {Nirmal J. Ghimire and Rebecca L. Dally and L. Poudel and D. C. Jones and D. Michel and N. Thapa Magar and M. Bleuel and Michael A. McGuire and J. S. Jiang and J. F. Mitchell and Jeffrey W. Lynn and I. I. Mazin},

doi = {10.1126/sciadv.abe2680},

issn = {2375-2548},

year  = {2020},

date = {2020-12-01},

journal = {SCIENCE ADVANCES},

volume = {6},

number = {51},

publisher = {AMER ASSOC ADVANCEMENT SCIENCE},

address = {1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA},

abstract = {Identification, understanding, and manipulation of novel magnetic 

 textures are essential for the discovery of new quantum materials for 

 future spin-based electronic devices. In particular, materials that 

 manifest a large response to external stimuli such as a magnetic field 

 are subject to intense investigation. Here, we study the kagome-net 

 magnet YMn6Sn6 by magnetometry, transport, and neutron diffraction 

 measurements combined with first-principles calculations. We identify a 

 number of nontrivial magnetic phases, explain their microscopic nature, 

 and demonstrate that one of them hosts a large topological Hall effect 

 (THE). We propose a previously unidentified fluctuation-driven 

 mechanism, which leads to the THE at elevated temperatures. This 

 interesting physics comes from parametrically frustrated interplanar 

 exchange interactions that trigger strong magnetic fluctuations. Our 

 results pave a path to chiral spin textures, promising for novel 

 spintronics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000585253900004,

title = {Density functional theory-based electric field gradient database},

author = {Kamal Choudhary and Jaafar N. Ansari and Igor I. Mazin and Karen L. Sauer},

doi = {10.1038/s41597-020-00707-8},

year  = {2020},

date = {2020-10-01},

journal = {SCIENTIFIC DATA},

volume = {7},

number = {1},

publisher = {NATURE RESEARCH},

address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY},

abstract = {The deviation of the electron density around the nuclei from spherical 

 symmetry determines the electric field gradient (EFG), which can be 

 measured by various types of spectroscopy. Nuclear Quadrupole Resonance 

 (NQR) is particularly sensitive to the EFG. The EFGs, and by implication 

 NQR frequencies, vary dramatically across materials. Consequently, 

 searching for NQR spectral lines in previously uninvestigated materials 

 represents a major challenge. Calculated EFGs can significantly aid at 

 the search's inception. To facilitate this task, we have applied 

 high-throughput density functional theory calculations to predict EFGs 

 for 15187 materials in the JARVIS-DFT database. This database, which 

 will include EFG as a standard entry, is continuously increasing. Given 

 the large scope of the database, it is impractical to verify each 

 calculation. However, we assess accuracy by singling out cases for which 

 reliable experimental information is readily available and compare them 

 to the calculations. We further present a statistical analysis of the 

 results. The database and tools associated with our work are made 

 publicly available by JARVIS-DFT (https://www.ctcms.nist.gov/similar to 

 knc6/JVASP.html) and NIST-JARVIS API (http://jarvis.nist.gov/).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000542638200001,

title = {Enhanced performance of In(2)O(3)nanowire field effect transistors with 

 controllable surface functionalization of Ag nanoparticles},

author = {Liming Wu and Jinxia Xu and Qiliang Li and Zhicheng Fan and Fei Mei and Yuanming Zhou and Jiang Yan and Ying Chen},

doi = {10.1088/1361-6528/ab8f4a},

issn = {0957-4484},

year  = {2020},

date = {2020-08-01},

journal = {NANOTECHNOLOGY},

volume = {31},

number = {35},

publisher = {IOP PUBLISHING LTD},

address = {TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND},

abstract = {Indium oxide (In2O3) nanowire field effect transistors (FETs) have great 

 potential in electronic and sensor applications owing to their suitable 

 band width and high electron mobility. However, the In(2)O(3)nanowire 

 FETs reported previously were operated in a depletion-mode, not suitable 

 to the integrated circuits result of the high-power consumption. 

 Therefore, tuning the electrical properties of In(2)O(3)nanowire FETs 

 into enhancement-mode is critical for the successful application in the 

 fields of high-performance electronics, optoelectronics and detectors. 

 In the work, a simple but effective strategy was carried out by 

 preparing Ag nanoparticle functionalized In(2)O(3)NWs to regulate the 

 threshold voltage (V-th) of In2O3NW FETs, successfully achieving 

 enhanced-mode devices. The threshold voltage can be regulated from -6.9 

 V to +7 V by controlling Ag density via deposition time. In addition, 

 the devices exhibited high performance: huge I-on/I(off)ratio > 10(8), 

 large maximum saturation current approximate to 800 mA and excellent 

 carrier mobility approximate to 129 cm(2)Vcs(-1). The enhanced 

 performance is attributed to the surface passivation by Ag nanoparticles 

 to reduce the density of traps and the charge transfer between traps and 

 the nanowires to regulate the V-th. The result indicates the application 

 of metal nanoparticles significantly improve oxide NW for low-power 

 FETs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000597804100005,

title = {Finite-momentum condensate brought on by a Zeeman field},

author = {Stephen Keeling and Predrag Nikolic},

doi = {10.1103/PhysRevA.102.063310},

issn = {2469-9926},

year  = {2020},

date = {2020-12-01},

journal = {PHYSICAL REVIEW A},

volume = {102},

number = {6},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We study superfluid states in a two-dimensional fermionic attractive 

 Hubbard model with Zeeman coupling to an external field. Focusing our 

 attention on singlet pairing in both weak and strong coupling regimes, 

 we reveal a rich phase diagram of finite-momentum condensates which 

 exhibits both Fulde-Ferrell and Larkin-Ovchinnikov orders at zero 

 temperature. The latter are commensurate stripe states that 

 spontaneously break a lattice symmetry; many stable ordering wave 

 vectors are found as a function of particle density and a Zeeman field. 

 Stronger coupling significantly enhances the stability of the 

 finite-momentum condensates, but our numerical mean-field calculations 

 underestimate the effect of fluctuations and indicate a possible 

 localization near half filling.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000543153400041,

title = {Functionalization of GaN Nanowire Sensors With Metal Oxides: An 

 Experimental and DFT Investigation},

author = {Md Ashfaque Hossain Khan and Brian Thomson and Abhishek Motayed and Qiliang Li and Mulpuri V Rao},

doi = {10.1109/JSEN.2020.2978221},

issn = {1530-437X},

year  = {2020},

date = {2020-07-01},

journal = {IEEE SENSORS JOURNAL},

volume = {20},

number = {13},

pages = {7138-7147},

publisher = {IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC},

address = {445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA},

abstract = {The detection of NO2 molecules by GaN nanowire sensors which were 

 functionalized with various metal oxides have been comprehensively 

 studied with device fabrication, characterization and modeling with 

 first-principles calculations based on density functional theory (DFT). 

 In this work, GaN nanowires were prepared on Si substrate by standard 

 top-down fabrication process and then fabricated into resistor based 

 chemical sensors. The surface of GaN nanowires were functionalized by 

 three metal oxides: TiO2, ZnO and SnO2 for analysis. The UV illuminated 

 device characterization results indicated that the devices with TiO2 

 functionalization exhibited the highest response toward NO2 gas. It 

 showed quick response (240s) and recovery (280s) process with strong NO2 

 selectivity. In modeling, the oxide functionalized GaN in contact with 

 NO2 molecule was designed and geometrically optimized. Simulation 

 results indicated that TiO2 functionalization enabled the most energy 

 favorable surface for NO2 adsorption among the three metal oxides. In 

 addition, the electronic properties of these oxide functionalized GaN 

 have been studied in terms of the total density of states (TDOS) and 

 projected density of states (PDOS), indicating an excellent agreement 

 with the above-mentioned experimental measurements. Furthermore, the 

 effect of environmental humidity on the adsorbate-nanocomposite 

 interaction has been simulated and studied. Overall, the metal oxide 

 functionalization significantly enhances the performance of GaN gas 

 sensors and selecting an appropriate oxide will optimize the detection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000599507100026,

title = {Growth Kinetics and Atomistic Mechanisms of Native Oxidation of 

 ZrSxSe2-x and MoS2 Crystals},

author = {Seong Soon Jo and Akshay Singh and Liqiu Yang and Subodh C. Tiwari and Sungwook Hong and Aravind Krishnamoorthy and Maria Gabriela Sales and Sean M. Oliver and Joshua Fox and Randal L. Cavalero and David W. Snyder and Patrick M. Vora and Stephen J. McDonnell and Priya Vashishta and Rajiv K. Kalia and Aiichiro Nakano and R. Jaramillo},

doi = {10.1021/acs.nanolett.0c03263},

issn = {1530-6984},

year  = {2020},

date = {2020-12-01},

journal = {NANO LETTERS},

volume = {20},

number = {12},

pages = {8592-8599},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

abstract = {A thorough understanding of native oxides is essential for designing 

 semiconductor devices. Here, we report a study of the rate and 

 mechanisms of spontaneous oxidation of bulk single crystals of ZrSxSe2-x 

 alloys and MoS2. ZrSxSe2-x alloys oxidize rapidly, and the oxidation 

 rate increases with Se content. Oxidation of basal surfaces is initiated 

 by favorable O-2 adsorption and proceeds by a mechanism of Zr-O bond 

 switching, that collapses the van der Waals gaps, and is facilitated by 

 progressive redox transitions of the chalcogen. The rate-limiting 

 process is the formation and out-diffusion of SO2. In contrast, MoS2 

 basal surfaces are stable due to unfavorable oxygen adsorption. Our 

 results provide insight and quantitative guidance for designing and 

 processing semiconductor devices based on ZrSxSe2-x and MoS2 and 

 identify the atomistic-scale mechanisms of bonding and phase 

 transformations in layered materials with competing anions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000575037700001,

title = {Ising Superconductivity and Magnetism in NbSe2},

author = {Darshana Wickramaratne and Sergii Khmelevskyi and Daniel F. Agterberg and I. I. Mazin},

doi = {10.1103/PhysRevX.10.041003},

issn = {2160-3308},

year  = {2020},

date = {2020-10-01},

journal = {PHYSICAL REVIEW X},

volume = {10},

number = {4},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Recent studies on superconductivity in NbSe2 have demonstrated a large 

 anisotropy in the superconducting critical field when the material is 

 reduced to a single monolayer. Motivated by this recent discovery, we 

 use density-functional theory (DFT) calculations to quantitatively 

 address the superconducting properties of bulk and monolayer NbSe2. We 

 demonstrate that NbSe2 is close to a ferromagnetic instability, and 

 analyze our results in the context of experimental measurements of the 

 spin susceptibility in NbSe2. We show how this magnetic instability, 

 which is pronounced in a single monolayer, can enable sizable 

 singlet-triplet mixing of the superconducting order parameter, contrary 

 to contemporary considerations of the pairing symmetry in monolayer 

 NbSe2, and discuss approaches as to how this degree of mixing can be 

 addressed quantitatively within our DFT framework. Our calculations also 

 enable a quantitative description of the large anisotropy of the 

 superconducting critical field, using DFT calculations of monolayer 

 NbSe2 in the normal state.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000536478700006,

title = {Laser-induced photothermal generation of flexible and salt-resistant 

 monolithic bilayer membranes for efficient solar desalination},

author = {Minsu Kim and Kwansoo Yang and Yong Seok Kim and Jong Chan Won and Pilgyu Kang and Yun Ho Kim and Byoung Gak Kim},

doi = {10.1016/j.carbon.2020.03.059},

issn = {0008-6223},

year  = {2020},

date = {2020-08-01},

journal = {CARBON},

volume = {164},

pages = {349-356},

publisher = {PERGAMON-ELSEVIER SCIENCE LTD},

address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND},

abstract = {Harvesting solar energy and generating steam through solar thermal 

 energy are viable approaches with diverse applications such as power 

 generation, desalination, and water purification. Particularly, for 

 efficient and stable solar desalination, hierarchically porous materials 

 are desired to enable the required multiple functionalities. However, 

 high thermal/chemical energy required and time consumed remain 

 roadblocks. In this study, a facile, fast, and scalable laser-induced 

 photothermal method to achieve flexible monolithic bilayer sheets (MBS) 

 of hierarchically porous graphitic carbon (HPGC) and polymeric foam for 

 use in salt-resistant and flexible solar steam generators is reported. 

 The MBS-based self-floating solar steam generator shows outstanding 

 solar desalination performance with a solar thermal efficiency of 83.2% 

 (1-sun) and a high salt-rejection ratio (99.9%). Efficient solar 

 thermal energy transformation is achieved by the versatile 

 multi-functionalities of the MBS, including broad-spectrum solar light 

 absorption, heat localization, and capillary action. Anisotropic wetting 

 properties of hydrophobic HPGC and hydrophilic polyimide (PI) foam 

 effectively prevent salt accumulation on the HPGC surface. The 

 salt-resistant MBS enable long-term stability for solar desalination 

 with actual seawater. Our laser-based photothermal method has potential 

 in the development of high-performance solar thermal systems with 

 substantial cost reduction by scalable production of multiscale 

 hierarchically structured materials from micro-structured polymers. (C) 

 2020 Elsevier Ltd. All rights reserved.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000557762800074,

title = {Localized Excitons in NbSe2-MoSe2 Heterostructures},

author = {Jaydeep Joshi and Tong Zhou and Sergiy Krylyuk and Albert V. Davydov and Igor Zutic and Patrick M. Vora},

doi = {10.1021/acsnano.0c02803},

issn = {1936-0851},

year  = {2020},

date = {2020-07-01},

journal = {ACS NANO},

volume = {14},

number = {7},

pages = {8528-8538},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

abstract = {Neutral and charged excitons (trions) in atomically thin materials offer 

 important capabilities for photonics, from ultrafast photodetectors to 

 highly efficient light-emitting diodes and lasers. Recent studies of van 

 der Waals (vdW) heterostructures comprised of dissimilar monolayer 

 materials have uncovered a wealth of optical phenomena that are 

 predominantly governed by interlayer interactions. Here, we examine the 

 optical properties in NbSe2-MoSe2 vdW heterostructures, which provide an 

 important model system to study metal-semiconductor interfaces, a common 

 element in optoelectronics. Through low-temperature photoluminescence 

 (PL) microscopy, we discover a sharp emission feature, L1, that is 

 localized at the NbSe2-capped regions of MoSe2. L1 is observed at 

 energies below the commonly studied MoSe2 excitons and trions and 

 exhibits temperature- and power-dependent PL consistent with exciton 

 localization in a confining potential. This PL feature is robust, 

 observed in a variety of samples fabricated with different stacking 

 geometries and cleaning procedures. Using first-principles calculations, 

 we reveal that the confinement potential required for exciton 

 localization naturally arises from the in-plane band bending due to the 

 changes in the electron affinity between pristine MoSe2 and NbSe2-MoSe2 

 heterostructure. We discuss the implications of our studies for 

 atomically thin optoelectronics devices with atomically sharp interfaces 

 and tunable electronic structures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000537315300006,

title = {Magnetic impurities in Kondo insulators: An application to samarium 

 hexaboride},

author = {W. T. Fuhrman and P. Nikolic},

doi = {10.1103/PhysRevB.101.245118},

issn = {2469-9950},

year  = {2020},

date = {2020-06-01},

journal = {PHYSICAL REVIEW B},

volume = {101},

number = {24},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Impurities and defects in Kondo insulators can have an unusual impact on 

 dynamics that blends with effects of intrinsic electron correlations. 

 Such crystal imperfections are difficult to avoid, and their 

 consequences are incompletely understood. Here we study magnetic 

 impurities in Kondo insulators via perturbation theory of the s-d Kondo 

 impurity model adapted to small-band-gap insulators. The calculated 

 magnetization and specific heat agree with recent thermodynamic 

 measurements in samarium hexaboride (SmB6). This qualitative agreement 

 supports the physical picture of multichannel Kondo screening of local 

 moments by electrons and holes involving both intrinsic and impurity 

 bands. Specific heat is thermally activated in zero field by Kondo 

 screening through subgap impurity bands and exhibits a characteristic 

 upturn as the temperature is decreased. In contrast, magnetization 

 obtains a dominant quantum correction from partial screening by virtual 

 particle-hole pairs in intrinsic bands. We point out that magnetic 

 impurities could impact de Haas-van Alphen quantum oscillations in SmB6, 

 through the effects of Landau quantization in intrinsic bands on the 

 Kondo screening of impurity moments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000598977600071,

title = {Maritime vessel emission monitoring by an UAV gas sensor system},

author = {Haiwen Yuan and Changshi Xiao and Yanfeng Wang and Xin Peng and Yuanqiao Wen and Qiliang Li},

doi = {10.1016/j.oceaneng.2020.108206},

issn = {0029-8018},

year  = {2020},

date = {2020-12-01},

journal = {OCEAN ENGINEERING},

volume = {218},

publisher = {PERGAMON-ELSEVIER SCIENCE LTD},

address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND},

abstract = {Monitoring the gas emission of maritime vessels is very challenging as 

 the fields are almost inaccessible and the emission is very susceptible 

 to the surrounding environment. In ultra-large-scale maritime scenes, 

 mobile robots capable of gas detection and tracking will most likely 

 fall into atmospheric turbulence. In this work, an enhanced tracking 

 algorithm using our unmanned aerial vehicle (UAV) gas sensor system is 

 proposed for maritime vessel emission monitoring. A global prediction is 

 acquired by modelling the emission of individual vessel, while another 

 local gradient direction can be calculated from the real-time onboard 

 sensor measurements. By a probabilistic framework, the global prediction 

 and the gradient detection are fused to generate a more reliable 

 navigation for the UAV. In order to verify the proposed algorithm, real 

 monitoring experiments using the developed UAV gas sensor system are 

 presented and SO2, NOx contents in vessel emissions are conducted. A 

 comparison between the UAV-based detections and the off-line sampled 

 data is preformed, and the results indicate that the proposed algorithm 

 has the advantage in exactly guiding the UAV towards the vessel 

 emission.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000506719400071,

title = {New Alternating Current Noise Analytics Enables High Discrimination in 

 Gas Sensing},

author = {Huixian Ye and Chen Shi and Jiang Li and Li Tian and Min Zeng and Hui Wang and Qiliang Li},

doi = {10.1021/acs.analchem.9b03312},

issn = {0003-2700},

year  = {2020},

date = {2020-01-01},

journal = {ANALYTICAL CHEMISTRY},

volume = {92},

number = {1},

pages = {824-829},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

abstract = {Feature analysis has been increasingly considered as an important way to 

 enhance the discrimination performance of gas sensors. In this work, a 

 new analytical method based on alternating current noise spectrum is 

 developed to discriminate chemically and structurally similar gases with 

 remarkable performance. Compared with the conventional analytics based 

 on the maximum, integral, and time of response, the noise spectrum of 

 electrical response introduces a new informative feature to discriminate 

 chemical gases. In experiment, three chemically and structurally similar 

 gases, mesitylene, toluene, and o-xylene, are tested on ZnO thin film 

 gas sensors. The result indicated that the noise analytics assisted by 

 the support vector machine algorithm discriminated these similar gases 

 with 94.2% in precision, about 20% higher than those alternating 

 current noise analytics is very promising for application in 

 sensorsobtained by conventional methods. Such a new for high 

 discrimination precision.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000560962500003,

title = {Quantum field theory of topological spin dynamics},

author = {Predrag Nikolic},

doi = {10.1103/PhysRevB.102.075131},

issn = {2469-9950},

year  = {2020},

date = {2020-08-01},

journal = {PHYSICAL REVIEW B},

volume = {102},

number = {7},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We develop a field theory of quantum magnets and magnetic (semi)metals, 

 which is suitable for the analysis of their universal and topological 

 properties. The systems of interest include collinear, coplanar, and 

 general noncoplanar magnets. At the basic level, we describe the 

 dynamics of magnetic moments using smooth vector fields in the continuum 

 limit. Dzyaloshinskii-Moriya interaction is captured by a non-Abelian 

 vector gauge field, and chiral spin couplings related to topological 

 defects appear as higher-rank antisymmetric tensor gauge fields. We 

 distinguish type-I and type-II magnets by their equilibrium response to 

 the non-Abelian gauge flux, and characterize the resulting lattices of 

 skyrmions and hedgehogs, the spectra of spin waves, and the chiral 

 response to external perturbations. The general spin-orbit coupling of 

 electrons is similarly described by non-Abelian gauge fields, including 

 higher-rank tensors related to the electronic Berry flux. Itinerant 

 electrons and local moments exchange their gauge fluxes through Kondo 

 and Hund interactions. Hence, by utilizing gauge fields, this theory 

 provides a unifying physical picture of ``intrinsic'' and 

 ``topological'' anomalous Hall effects, spin-Hall effects, and other 

 correlations between the topological properties of electrons and 

 moments. We predict ``topological'' magnetoelectric effect in 

 materials prone to hosting hedgehogs. Links to experiments and model 

 calculations are provided by deriving the couplings and gauge fields 

 from generic microscopic models, including the Hubbard model with 

 spin-orbit interactions. Much of the formal analysis is generalized to d 

 spatial dimensions in order to access the pi(d-1)(Sd-1) homotopy 

 classification of the magnetic hedgehog topological defects, and 

 establish the possibility of novel quantum spin liquids that exhibit a 

 fractional magnetoelectric effect. However, we emphasize the form of all results in the physically relevant d = 3 dimensions, and discuss a few 

 applications to topological magnetic conductors like Mn3Sn and Pr2Ir2O7.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000589801000007,

title = {Recent advances in developing organic electrode materials for 

 multivalent rechargeable batteries},

author = {Kaiqiang Qin and Jinghao Huang and Kathryn Holguin and Chao Luo},

doi = {10.1039/d0ee02111c},

issn = {1754-5692},

year  = {2020},

date = {2020-11-01},

journal = {ENERGY \& ENVIRONMENTAL SCIENCE},

volume = {13},

number = {11},

pages = {3950-3992},

publisher = {ROYAL SOC CHEMISTRY},

address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, 

 ENGLAND},

abstract = {Due to the low cost and abundance of multivalent metallic resources 

 (Mg/Al/Zn/Ca), multivalent rechargeable batteries (MRBs) are promising 

 alternatives to Li-ion and Pb-acid batteries for grid-scale stationary 

 energy storage applications. However, the high performance of inorganic 

 electrode materials in Li-ion batteries does not extend to MRBs, because 

 the high charge density of multivalent cations dramatically reduces 

 their diffusivity in the crystal lattice of inorganic materials. To 

 achieve high-performance MRBs, organic electrode materials (OEMs) with 

 abundant structural diversity and high structural tunability offer 

 opportunities. This review presents an overview of the state-of-the-art 

 OEMs in MRBs, including non-aqueous rechargeable Mg/Al/Zn and aqueous 

 rechargeable Mg/Al/Zn/Ca batteries. The advantages, challenges, 

 development, mechanism, structure, and performance of OEMs in MRBs are 

 discussed in detail. To provide a comprehensive and thorough 

 understanding of OEMs in MRBs, the correlation between molecular 

 structure and electrochemical behavior is also summarized and discussed. 

 This review offers insights for the rational structure design and 

 performance optimization of advanced OEMs in MRBs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000590411700008,

title = {Reduction of the Spin Susceptibility in the Superconducting State of 

 Sr2RuO4 Observed by Polarized Neutron Scattering},

author = {A. N. Petsch and M. Zhu and Mechthild Enderle and Z. Q. Mao and Y. Maeno and I. I. Mazin and S. M. Hayden},

doi = {10.1103/PhysRevLett.125.217004},

issn = {0031-9007},

year  = {2020},

date = {2020-11-01},

journal = {PHYSICAL REVIEW LETTERS},

volume = {125},

number = {21},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Recent observations [A. Pustogow et al., Nature (London) 574, 72 

 (2019).] of a drop of the O-17 nuclear magnetic resonance (NMR) Knight 

 shift in the superconducting state of Sr2RuO4 challenged the popular 

 picture of a chiral odd-parity paired state in this compound. Here we 

 use polarized neutron scattering (PNS) to show that there is a 34 +/- 

 6% drop in the magnetic susceptibility at the Ru site below the 

 superconducting transition temperature. We measure at lower fields H 

 similar to( )1/3 H-c2 than a previous PNS study allowing the suppression 

 to be observed. The PNS measurements show a smaller susceptibility 

 suppression than NMR measurements performed at similar field and temperature. Our results rule out the chiral odd-parity d = (z) over cap 

 (k(x) +/- ik(y)) state and are consistent with several recent proposals 

 for the order parameter including even-parity B-1g and odd-parity 

 helical states.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000577073300002,

title = {Superconductivity in La2Ni2In},

author = {Jannis Maiwald and Igor I. Mazin and Alex Gurevich and Meigan Aronson},

doi = {10.1103/PhysRevB.102.165125},

issn = {2469-9950},

year  = {2020},

date = {2020-10-01},

journal = {PHYSICAL REVIEW B},

volume = {102},

number = {16},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We report here the properties of single crystals of La2Ni2In. Electrical 

 resistivity and specific heat measurements concur with the results of 

 density functional theory calculations, finding that La2Ni2In is a 

 weakly correlated metal, where the Ni magnetism is almost completely 

 quenched, leaving only a weak Stoner enhancement of the density of 

 states. Superconductivity is observed at temperatures below 0.9 K. A 

 detailed analysis of the field and temperature dependencies of the 

 resistivity, magnetic susceptibility, and specific heat at the lowest 

 temperatures reveals that La2Ni2In is a dirty type-II superconductor 

 with likely s-wave gap symmetry. Nanoclusters of ferromagnetic 

 inclusions significantly affect the subgap states resulting in a 

 nonexponential temperature dependence of the specific heat C(T) at T << 

 T-c.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000511169400007,

title = {Topology and correlations on the kagome lattice},

author = {Nirmal J Ghimire and Igor I Mazin},

doi = {10.1038/s41563-019-0589-8},

issn = {1476-1122},

year  = {2020},

date = {2020-02-01},

journal = {NATURE MATERIALS},

volume = {19},

number = {2},

pages = {137-138},

publisher = {NATURE PUBLISHING GROUP},

address = {MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND},

abstract = {Both a Dirac band and a flat band - signatures of topology and 

 correlation - are found in a prototypical antiferromagnetic kagome 

 lattice compound FeSn.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000510146500006,

title = {Tuning single-electron charging and interactions between compressible 

 Landau level islands in graphene},

author = {Daniel Walkup and Fereshte Ghahari and Christopher Gutierrez and Kenji Watanabe and Takashi Taniguchi and Nikolai B Zhitenev and Joseph A Stroscio},

doi = {10.1103/PhysRevB.101.035428},

issn = {2469-9950},

year  = {2020},

date = {2020-01-01},

journal = {PHYSICAL REVIEW B},

volume = {101},

number = {3},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Interacting and tunable quantum dots (QDs) have been extensively 

 exploited in condensed matter physics and quantum information science. 

 Using a low-temperature scanning tunneling microscope (STM), we both 

 create and directly image a new type of coupled QD system in graphene, a 

 highly interacting quantum relativistic system with tunable density. 

 Using detailed scanning tunneling spectroscopy (STS) measurements, we 

 show that Landau quantization inside a potential well enables novel 

 electron confinement via the incompressible strips between partially 

 filled Landau levels (LLs), forming isolated and concentric LL QDs. By 

 changing the charge density and the magnetic field we can tune 

 continuously between single- and double-concentric LL QD systems within 

 the same potential well. In the concentric QD regime, single-electron 

 charging peaks of the two dots intersect, displaying a characteristic 

 avoidance pattern. At moderate fields, we observe an unconventional 

 avoidance pattern that differs significantly from that observed in 

 capacitively coupled double-QD systems. We find that we can reproduce in 

 detail this anomalous avoidance pattern within the framework of the 

 electrostatic double-QD model by replacing the capacitive interdot 

 coupling with a phenomenological charge-counting system in which charges 

 in the inner concentric dot are counted in the total charge of both 

 islands. The emergence of such strange forms of interdot coupling in a 

 single potential well, together with the ease of producing such charge 

 pockets in graphene and other two-dimensional (2D) materials, reveals an 

 intriguing testbed for the confinement of 2D electrons in customizable 

 potentials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000594089300010,

title = {Ultrafast dynamics in the high-symmetry and in the charge density wave 

 phase of 2H-NbSe2},

author = {A. Anikin and R. D. Schaller and G. P. Wiederrecht and E. R. Margine and I. I. Mazin and G. Karapetrov},

doi = {10.1103/PhysRevB.102.205139},

issn = {2469-9950},

year  = {2020},

date = {2020-11-01},

journal = {PHYSICAL REVIEW B},

volume = {102},

number = {20},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {We investigate carrier and collective mode dynamics in 2H-NbSe2 using 

 time-resolved optical pump-probe spectroscopy and compare the results 

 with first-principles calculations. Broadband ultrafast reflectivity 

 studies of 2H-NbSe2 in a wide temperature interval covering the normal, 

 charge density wave (CDW) and superconducting phase were performed. 

 Spectral features observed in the transient reflectivity experiment were 

 associated with specific optical transitions obtained from band 

 structure calculations. Displacive excitation of coherent phonons showed 

 CDW-associated coherent oscillations of the soft phonon mode across the 

 whole spectral range. Temperature evolution of this coherent phonon mode 

 in the low-excitation linear regime shows softening of the mode down to 

 the CDW transition temperature T-CDW with subsequent hardening below 

 T-CDW. The global fit of the broadband probe data reveals four different 

 relaxation times associated with characteristic electron-electron, 

 electron-phonon, and phonon-phonon relaxation processes. From 

 first-principles calculations of electron-phonon coupling we associate 

 the few picosecond electron-phonon relaxation time tau(2) with a 

 specific group of phonons with frequencies around 20 meV. On the other 

 hand, the anomalously long relaxation time of tau(3) similar to 100 ps 

 is associated with anharmonicity-driven phonon-phonon scattering. All 

 relaxation processes result from anomalies near the second order CDW 

 phase transition that are reflected in the temperature dependencies of 

 the characteristic relaxation times and amplitudes of coherent 

 oscillations. At the highest fluences we observe electronic melting of 

 the CDW and disappearance of the mode hardening below T-CDW.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000510920900001,

title = {Valley phenomena in the candidate phase change material WSe2(1-x)Te2x},

author = {Sean M Oliver and Joshua Young and Sergiy Krylyuk and Thomas L Reinecke and Albert V Davydov and Patrick M Vora},

doi = {10.1038/s42005-019-0277-7},

issn = {2399-3650},

year  = {2020},

date = {2020-01-01},

journal = {COMMUNICATIONS PHYSICS},

volume = {3},

number = {1},

publisher = {NATURE PUBLISHING GROUP},

address = {MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND},

abstract = {Alloyed transition metal dichalcogenides provide a route toward 

 atomically-thin phase change memories that host valleytronic behaviours. 

 Here, Raman and photoluminescence spectroscopies are employed to 

 demonstrate the robustness of valley polarisation to chemical 

 substitution in monolayer alloys. 

 Alloyed transition metal dichalcogenides provide an opportunity for 

 coupling band engineering with valleytronic phenomena in an 

 atomically-thin platform. However, valley properties in alloys remain 

 largely unexplored. We investigate the valley degree of freedom in 

 monolayer alloys of the phase change candidate material WSe2(1-x)Te2x. 

 Low temperature Raman measurements track the alloy-induced transition 

 from the semiconducting 1H phase of WSe2 to the semimetallic 1T(d) phase 

 of WTe2. We correlate these observations with density functional theory 

 calculations and identify new Raman modes from W-Te vibrations in the 

 1H-phase alloy. Photoluminescence measurements show ultra-low energy 

 emission features that highlight alloy disorder arising from the large 

 W-Te bond lengths. Interestingly, valley polarization and coherence in 

 alloys survive at high Te compositions and are more robust against 

 temperature than in WSe2. These findings illustrate the persistence of 

 valley properties in alloys with highly dissimilar parent compounds and 

 suggest band engineering can be utilized for valleytronic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000478860505402,

title = {DFT analysis of Raman modes in the CDW states of layered 2H-TaSe2 and 

 2H-TaS2},

author = {Sugata Chowdhury and Heather Hill and Jeffrey Simpson and Patrick Vora and Angela Hight Walker and Francesca Tavazza},

issn = {0065-7727},

year  = {2019},

date = {2019-03-01},

journal = {ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY},

volume = {257},

publisher = {AMER CHEMICAL SOC},

address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},

organization = {Amer Chem Soc},

note = {National Meeting of the American-Chemical-Society (ACS), Orlando, FL, 

 MAR 31-APR 04, 2019},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hu2019,

title = {Dynamical singularities of Floquet higher-order topological insulators},

author = {Haiping Hu and Biao Huang and Erhai Zhao and Vincent W Liu},

url = {http://arxiv.org/abs/1905.03727},

year  = {2019},

date = {2019-05-01},

abstract = {We propose a versatile framework to dynamically generate Floquet higher-order topological insulators by multi-step driving of topologically trivial Hamiltonians. Two analytically solvable examples are used to illustrate this procedure to yield Floquet quadrupole and octupole insulators with zero- and/or $backslashpi$-corner modes protected by mirror symmetries. We introduce dynamical topological invariants from the full unitary return map and show its phase bands contain Weyl singularities whose topological charges form dynamical multipole moments in the Brillouin zone. Combining them with the topological index of Floquet Hamiltonian gives a pair of $backslashmathbbZ_2$ invariant $backslashnu_0$ and $backslashnu_backslashpi$ which fully characterize the higher-order topology and predict the appearance of zero- and $backslashpi$-corner modes. Our work establishes a systematic route to construct and characterize Floquet higher-order topological phases.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zou2019,

title = {Exactly Solvable Points and Symmetry Protected Topological Phases of Quantum Spins on a Zig-Zag Lattice},

author = {Haiyuan Zou and Erhai Zhao and Xi-Wen Guan and Vincent W Liu},

url = {https://link.aps.org/doi/10.1103/PhysRevLett.122.180401},

doi = {10.1103/PhysRevLett.122.180401},

issn = {0031-9007},

year  = {2019},

date = {2019-05-01},

journal = {Physical Review Letters},

volume = {122},

number = {18},

pages = {180401},

abstract = {A large number of symmetry-protected topological (SPT) phases have been hypothesized for strongly interacting spin-1/2 systems in one dimension. Realizing these SPT phases, however, often demands fine-tunings hard to reach experimentally. And the lack of analytical solutions hinders the understanding of their many-body wave functions. Here we show that two kinds of SPT phases naturally arise for ultracold polar molecules confined in a zigzag optical lattice. This system, motivated by recent experiments, is described by a spin model whose exchange couplings can be tuned by an external field to reach parameter regions not studied before for spin chains or ladders. Within the enlarged parameter space, we find the ground state wave function can be obtained exactly along a line and at a special point, for these two phases respectively. These exact solutions provide a clear physical picture for the SPT phases and their edge excitations. We further obtain the phase diagram by using infinite time-evolving block decimation, and discuss the phase transitions between the two SPT phases and their experimental signatures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000487038900006,

title = {High-performance room-temperature TiO2-functionalized GaN nanowire gas 

 sensors},

author = {Chen Shi and Asha Rani and Brian Thomson and Ratan Debnath and Abhishek Motayed and Dimitris E Ioannou and Qiliang Li},

doi = {10.1063/1.5116677},

issn = {0003-6951},

year  = {2019},

date = {2019-09-01},

journal = {APPLIED PHYSICS LETTERS},

volume = {115},

number = {12},

publisher = {AMER INST PHYSICS},

address = {1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA},

abstract = {Hybrid gas sensors based on TiO2 functionalized gallium nitride 

 nanowires have been prepared by nanofabrication and comprehensively 

 studied for high-responsivity applications. The devices exhibited a high 

 responsivity (25%) to 500 ppm NO2 assisted with ultraviolet 

 illumination at room temperature. The thickness and doping concentration 

 of TiO2 were engineered to improve the transducer function. The result 

 indicated that an excellent n-type response can be stably obtained for a 

 doping range from 1 x 10(17) cm(-3) to 1 x 10(19) cm(-3). The TiO2 

 thickness and doping concentration can be further fine-tuned to achieve 

 optimal performance. In addition, a comprehensive device simulation was 

 carried out to understand the device operation and gain insight for 

 optimizing the device performance.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000503750200015,

title = {Nonvolatile memory based on redox-active ruthenium molecular monolayers},

author = {Kai Jiang and Sujitra J Pookpanratana and Tong Ren and Sean N Natoli and Brent A Sperling and Joseph Robertson and Curt A Richter and Sheng Yu and Qiliang Li},

doi = {10.1063/1.5108675},

issn = {0003-6951},

year  = {2019},

date = {2019-10-01},

journal = {APPLIED PHYSICS LETTERS},

volume = {115},

number = {16},

publisher = {AMER INST PHYSICS},

address = {1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA},

abstract = {A monolayer of diruthenium molecules was self-assembled onto the silicon 

 oxide surface in a semiconductor capacitor structure with a ``click'' 

 reaction for nonvolatile memory applications. The attachment of the 

 active molecular monolayer was verified by x-ray photoelectron 

 spectroscopy. The prototypical capacitor memory devices in this work 

 employed a metal/oxide/molecule/oxide/Si structure. With the intrinsic 

 redox-active charge-storage properties of diruthenium molecules, these 

 capacitor memory devices exhibited fast Program and Erase speed, 

 excellent endurance performance with negligible degradation of the 

 memory window after 10(5) program/erase cycles, and very good 10-year 

 memory retention. These experimental results indicate that the 

 redox-active ruthenium molecular memory is very promising for use in 

 nonvolatile memory applications. Published under license by AIP 

 Publishing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000481469900038,

title = {Observation and control of the anomalous Aharonov-Bohm oscillation in 

 enhanced-mode topological insulator nanowire field-effect transistors},

author = {Hao Zhu and Curt A Richter and Sheng Yu and Huixian Ye and Min Zeng and Qiliang Li},

doi = {10.1063/1.5111180},

issn = {0003-6951},

year  = {2019},

date = {2019-08-01},

journal = {APPLIED PHYSICS LETTERS},

volume = {115},

number = {7},

publisher = {AMER INST PHYSICS},

address = {1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA},

abstract = {Aharonov-Bohm (AB) oscillation is a quantum mechanical phenomenon which 

 reveals the coupling of electromagnetic potentials with the electron 

 wave function, affecting the phase of the wave function. Such a quantum 

 interference effect can be demonstrated through the magnetotransport 

 measurement focusing on low-dimensional electronic states. Here, we 

 report the experimental observation of anomalous AB oscillation in an 

 enhanced-mode topological insulator Bi2Se3 nanowire field-effect 

 transistor (FET) under strong surface disorder, which is different from 

 the reported AB oscillation in topological insulator nanostructures. The 

 surrounding gate of the nanowire FET gives rise to tunability of the 

 chemical potential and introduces strong disorder on the surface states, 

 leading to primary oscillation with an anomalous h/e period. 

 Furthermore, the oscillation exhibits a significant dependence on the 

 gate voltage which has been preliminary explained with the quantization 

 of the surface conduction channel. The experimental demonstration can be 

 very attractive for further exploration of quantum phase interference 

 through electrical approaches, enabling applications in future 

 information and electromagnetic sensing technology.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Keles2019a,

title = {Phase diagram of Rydberg-dressed Fermi gas in two dimensions},

author = {Ahmet Keles and Erhai Zhao and Xiaopeng Li},

url = {http://arxiv.org/abs/1906.04235},

year  = {2019},

date = {2019-06-01},

abstract = {Rydberg-dressed ultracold Fermi gas is one of the latest quantum many-body systems where the sign, strength, and range of the interaction can be controlled experimentally. The interaction in momentum space has a negative minimum at $q_c$ inversely proportional to the characteristic length-scale in real space, the soft-core radius $r_c$. We show theoretically that single-component (spinless) Rydberg-dressed Fermi gas in two dimensions has a rich phase diagram with novel superfluid and density wave orders due to the interplay of the Fermi momentum $p_F$, interaction range $r_c$, and interaction strength $u_0$. For repulsive bare interactions $u_0textgreater0$, the dominant instability is $f$-wave superfluid for $p_Fr_cbackslashlesssim 2$, and density wave for $p_Fr_cbackslashgtrsim 4$. The $f$-wave pairing in a repulsive Fermi gas is reminiscent of, but differs from, the conventional Kohn-Luttinger mechanism. For attractive bare interactions $u_0textless0$, the leading instability is $p$-wave pairing with double degeneracy, which points to a $p_x+ip_y$ topological superfluid. The phase diagram is obtained from functional renormalization group with high momentum resolution. It treats all competing many-body instabilities in the particle-particle and particle-hole channels on equal footing beyond leading order perturbation theory and random-phase approximation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000471987400002,

title = {Piezoelectric enhancement of a defect-mediated boron nitride nanotube},

author = {Sheng Yu and Bagher Tabibi and Qiliang Li and Felix Jaetae Seo},

doi = {10.1088/1361-6463/ab2582},

issn = {0022-3727},

year  = {2019},

date = {2019-08-01},

journal = {JOURNAL OF PHYSICS D-APPLIED PHYSICS},

volume = {52},

number = {33},

publisher = {IOP PUBLISHING LTD},

address = {TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND},

abstract = {A zigzag boron nitride nanotube (ZBNNT) has a large intrinsic polarized 

 dipole and a piezoelectric tunability with crystal chirality, nanotube 

 diameter, and point defect. The piezoelectric coefficients (e(33)) of 

 8-ZBNNT with the VIA-group defects of S-N and Se-N are estimated to be 

 18.7 x 10(-2) C m(-2) and 14.9 x 10(-2) C m(-2), respectively. The 

 coefficients of defect-mediated 8-ZBNNT are 97% and 57% bigger than 

 that of pristine 8-ZBNNT. The elastic modulus of 8-ZBNNT is decreased 

 due to the VIA-group defects, but is increased for the larger number of 

 unit cells along zigzag rolling direction. The electronic band gap of 

 8-ZBNNT is reduced due to the VIA-group defects. The large 

 piezoelectricity enhancement of 8-ZBNNT with VIA-group defect is 

 attributable to the ionic contribution. Therefore, the unprecedented 

 defect-mediated 8-ZBNNT provides a new material platform of 

 mechanoelectronic devices for nanoscale sensors and energy conversions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zhang2019b,

title = {Probing the origin of lateral heterogeneities in synthetic monolayer molybdenum disulfide},

author = {Kehao Zhang and Yuanxi Wang and Jaydeep Joshi and Fu Zhang and Shruti Subramanian and Mauricio Terrones and Patrick Vora and Vincent Crespi and Joshua A Robinson},

url = {http://iopscience.iop.org/article/10.1088/2053-1583/aafd9a http://stacks.iop.org/2053-1583/6/i=2/a=025008?key=crossref.006e7cddfc7a7f13021280ae38e90026},

doi = {10.1088/2053-1583/aafd9a},

issn = {2053-1583},

year  = {2019},

date = {2019-02-01},

journal = {2D Materials},

volume = {6},

number = {2},

pages = {025008},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Keles2019b,

title = {Scrambling dynamics and many-body chaos in a random dipolar spin model},

author = {Ahmet Kele\c{s} and Erhai Zhao and Vincent W Liu},

url = {https://link.aps.org/doi/10.1103/PhysRevA.99.053620},

doi = {10.1103/PhysRevA.99.053620},

issn = {2469-9926},

year  = {2019},

date = {2019-05-01},

journal = {Physical Review A},

volume = {99},

number = {5},

pages = {053620},

abstract = {Is there a quantum many-body system that scrambles information as fast as a black hole? The Sachev-Ye-Kitaev model can saturate the conjectured bound for chaos, but it requires random all-to-all couplings of Majorana fermions that are hard to realize in experiments. Here we examine a quantum spin model of randomly oriented dipoles where the spin exchange is governed by dipole-dipole interactions. The model is inspired by recent experiments on dipolar spin systems of magnetic atoms, dipolar molecules, and nitrogen-vacancy centers. We map out the phase diagram of this model by computing the energy level statistics, spectral form factor, and out-of-time-order correlation (OTOC) functions. We find a broad regime of many-body chaos where the energy levels obey Wigner-Dyson statistics and the OTOC shows distinctive behaviors at different times: Its early-time dynamics is characterized by an exponential growth, while the approach to its saturated value at late times obeys a power law. The temperature scaling of the Lyapunov exponent $backslashlambda_L$ shows that while it is well below the conjectured bound $2backslashpi T$ at high temperatures, $backslashlambda_L$ approaches the bound at low temperatures and for large number of spins.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000473018900001,

title = {Short-range charge density wave order in 2H-TaS2},

author = {Jaydeep Joshi and Heather M Hill and Sugata Chowdhury and Christos D Malliakas and Francesca Tavazza and Utpal Chatterjee and Angela Hight R Walker and Patrick M Vora},

doi = {10.1103/PhysRevB.99.245144},

issn = {2469-9950},

year  = {2019},

date = {2019-06-01},

journal = {PHYSICAL REVIEW B},

volume = {99},

number = {24},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {2H-TaS2 undergoes a charge density wave (CDW) transition at T-CDW 

 similar to 75 K, however key questions regarding the onset of CDWorder 

 remain under debate. In this study, we explore the CDWtransition through 

 a combination of temperature and excitation-dependent Raman 

 spectroscopy, angle resolved photoemission spectroscopy (ARPES), and 

 density functional theory (DFT). Below T-CDW we identify two CDW 

 amplitude modes that redshift and broaden with increasing temperature 

 and one zone-folded mode that disappears above T-CDW. Above T-CDW, we 

 observe a strong two-phonon mode that softens substantially upon 

 cooling, which suggests the presence of substantial lattice distortions 

 at temperatures as high as 250 K. This correlates with the ARPES 

 observation of the persistence of a CDW energy gap above T-CDW and 

 finite-temperature DFT calculations of the phonon band structure that 

 indicate an instability occurring well above the CDW transition 

 temperature. DFT also provides the atomic displacements of the CDW 

 amplitude modes and reproduces their temperature dependence. From these 

 observations we suggest that short range CDW order exists well above 

 T-CDW, which poses new questions regarding the interplay between 

 electronic structure and vibrational modes in layered CDW materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vora2019,

title = {Strong coupling of a quantum dot molecule to a photonic crystal cavity},

author = {Patrick M Vora and Allan S Bracker and Samuel G Carter and Mijin Kim and Chul Soo Kim and Daniel Gammon},

url = {https://link.aps.org/doi/10.1103/PhysRevB.99.165420},

doi = {10.1103/PhysRevB.99.165420},

issn = {2469-9950},

year  = {2019},

date = {2019-04-01},

journal = {Physical Review B},

volume = {99},

number = {16},

pages = {165420},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000498263500022,

title = {The Predictive Power of Different Projector-Augmented Wave Potentials 

 for Nuclear Quadrupole Resonance},

author = {Jaafar N Ansari and Karen L Sauer and James K Glasbrenner},

doi = {10.3390/cryst9100507},

issn = {2073-4352},

year  = {2019},

date = {2019-10-01},

journal = {CRYSTALS},

volume = {9},

number = {10},

publisher = {MDPI},

address = {ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND},

abstract = {The projector-augmented wave (PAW) method is used to calculate electric 

 field gradients (EFG) for various PAW potentials. A variety of crystals 

 containing reactive nonmetal, simple metal, and transition elements, are 

 evaluated in order to determine the predictive ability of the PAW method 

 for the determination of nuclear quadrupole resonance frequencies in 

 previously unstudied materials and their polymorphs. All results were 

 compared to experimental results and, where possible, to previous 

 density functional theory (DFT) calculations. The EFG at the N-14 site 

 of NaNO2 is calculated by DFT for the first time. The reactive nonmetal 

 elements were not very sensitive to the variation in PAW potentials, and 

 calculations were quite close to experimental values. For the other 

 elements, the various PAW potentials led to a clear spread in EFG 

 values, with no one universal potential emerging. Within the spread, 

 there was agreement with other ab initio models.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ISI:000478991000003,

title = {V-51-NMR study on the S=1/2 square lattice antiferromagnet K2V3O8},

author = {H Takeda and H Yasuoka and M Yoshida and M Takigawa and N J Ghimire and D Mandrus and B C Sales},

doi = {10.1103/PhysRevB.100.054406},

issn = {2469-9950},

year  = {2019},

date = {2019-08-01},

journal = {PHYSICAL REVIEW B},

volume = {100},

number = {5},

publisher = {AMER PHYSICAL SOC},

address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},

abstract = {Static and dynamic properties of the quasi-two-dimensional 

 antiferromagnet K2V3O8 have been investigated by V-51-NMR experiments on nonmagnetic V5+ sites. Above the structural transition temperature T-S = 

 115 K, NMR spectra are fully compatible with the P4bm space-group 

 symmetry. The formation of superstructure below T-S causes splitting of 

 the NMR lines, which get broadened at lower temperatures so that 

 individual peaks are not well resolved. Evolution of NMR spectra with 

 magnetic field along the c axis below the magnetic transition 

 temperature T-N similar to 4 K is qualitatively consistent with a simple 

 Neel order and a spin-flop transition. However, a broad feature of the 

 spectra does not rule out possible incommensurate spin structure. The 

 spin-lattice relaxation rate 1/T-1 below T-N shows huge enhancement for 

 a certain range of magnetic field, which is independent of temperature 

 and attributed to cross relaxation due to anomalously large nuclear 

 spin-spin coupling between V5+ and magnetic V4+ sites. The results 

 indicate strong gapless spin fluctuations, which could arise from 

 incommensurate orders or complex spin textures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Oliver2019,

title = {Valley Phenomena in the Candidate Phase Change Material WSe$_2(1-x)$Te$_2x$},

author = {Sean M Oliver and Joshua Young and Sergiy Krylyuk and Thomas L Reinecke and Albert V Davydov and Patrick M Vora},

url = {http://arxiv.org/abs/1908.00506},

year  = {2019},

date = {2019-08-01},

abstract = {Alloyed transition metal dichalcogenides provide a unique opportunity for coupling band engineering and valleytronic phenomena in an atomically-thin platform. However, valley properties in alloys remain largely unexplored. We investigate the valley degree of freedom in monolayer alloys of the phase change candidate material WSe$_2(1-x)$Te$_2x$. Low temperature Raman measurements track the alloy-induced transition from the semiconducting 1H phase of WSe$_2$ to the semimetallic 1T$_d$ phase of WTe$_2$. We correlate these observations with density functional theory calculations and identify new Raman modes from 1H-WTe$_2$. Photoluminescence measurements show ultra-low energy emission features that highlight the presence of significant alloy disorder arising from the large W-Te bond lengths. Interestingly, valley polarization and coherence in alloys survive at high Te compositions and are more robust against temperature than in WSe$_2$. These findings illustrate the persistence of valley properties in alloys with highly dissimilar parent compounds and suggest band engineering can be utilized for valleytronic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevLett.120.187202,

title = {Absence of Long-Range Order in a Triangular Spin System with Dipolar Interactions},

author = {Ahmet Kele\c{s} and Erhai Zhao},

url = {https://link.aps.org/doi/10.1103/PhysRevLett.120.187202},

doi = {10.1103/PhysRevLett.120.187202},

issn = {0031-9007},

year  = {2018},

date = {2018-05-01},

journal = {Physical Review Letters},

volume = {120},

number = {18},

pages = {187202},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zhao2018_PRBRC_Collapsed,

title = {Collapsed tetragonal phase as a strongly covalent and fully nonmagnetic state: Persistent magnetism with interlayer As\textendashAs bond formation in Rh-doped Ca0.8 Sr0.2 Fe2 As2},

author = {K Zhao and J K Glasbrenner and H Gretarsson and D Schmitz and J Bednarcik and M Etter and J P Sun and R S Manna and A Al-Zein and S Lafuerza and W Scherer and J G Cheng and P Gegenwart},

url = {https://link.aps.org/doi/10.1103/PhysRevB.97.020510},

doi = {10.1103/PhysRevB.97.020510},

issn = {2469-9950},

year  = {2018},

date = {2018-01-01},

journal = {Physical Review B},

volume = {97},

number = {2},

pages = {020510},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Diaz2018,

title = {Increased Transfer Efficiency from Molecular Photonic Wires on Solid Substrates and Cryogenic Conditions},

author = {Sebasti\'{a}n A D\'{i}az and Sean M Oliver and David A Hastman and Igor L Medintz and Patrick M Vora},

url = {http://pubs.acs.org/doi/10.1021/acs.jpclett.8b00931},

doi = {10.1021/acs.jpclett.8b00931},

issn = {1948-7185},

year  = {2018},

date = {2018-07-01},

journal = {The Journal of Physical Chemistry Letters},

volume = {9},

number = {13},

pages = {3654--3659},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Diaz2018b,

title = {Increased Transfer Efficiency from Molecular Photonic Wires on Solid Substrates and Cryogenic Conditions},

author = {Sebasti\'{a}n A D\'{i}az and Sean M Oliver and David A Hastman and Igor L Medintz and Patrick M Vora},

url = {http://pubs.acs.org/doi/10.1021/acs.jpclett.8b00931},

doi = {10.1021/acs.jpclett.8b00931},

issn = {1948-7185},

year  = {2018},

date = {2018-07-01},

journal = {The Journal of Physical Chemistry Letters},

volume = {9},

number = {13},

pages = {3654--3659},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kang2018a,

title = {Mechanically reconfigurable architectured graphene for tunable plasmonic resonances},

author = {Pilgyu Kang and Kyoung-Ho Kim and Hong-Gyu Park and SungWoo Nam},

url = {http://www.nature.com/articles/s41377-018-0002-4},

doi = {10.1038/s41377-018-0002-4},

issn = {2047-7538},

year  = {2018},

date = {2018-12-01},

journal = {Light: Science \& Applications},

volume = {7},

number = {1},

pages = {17},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vega2018a,

title = {Photon echoes from an atomic frequency comb affected by population relaxation},

author = {Devin Vega and Mingzhen Tian},

url = {https://link.aps.org/doi/10.1103/PhysRevA.98.052340},

doi = {10.1103/PhysRevA.98.052340},

issn = {2469-9926},

year  = {2018},

date = {2018-11-01},

journal = {Physical Review A},

volume = {98},

number = {5},

pages = {052340},

abstract = {textcopyright 2018 American Physical Society. The atomic frequency comb (AFC) is a promising approach for quantum memory, yet creating an ideal AFC only in the ground-state population remains a challenge. We studied an imperfect AFC initially created in the population inversion between the excited and ground states and redistributed due to population relaxation in a three-level system where a long-lived metastable state plays a crucial role. A theoretical model has been developed to treat the storage of a weak input pulse and retrieval in the form of a photon echo. By comparing theory with experimental results we have studied the echo efficiency and overall attenuation of an input pulse in the AFC affected by both its initial spectral structure and the population relaxation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevB.97.245105,

title = {Renormalization group analysis of dipolar Heisenberg model on square lattice},

author = {Ahmet Kele\c{s} and Erhai Zhao},

url = {https://link.aps.org/doi/10.1103/PhysRevB.97.245105},

doi = {10.1103/PhysRevB.97.245105},

issn = {2469-9950},

year  = {2018},

date = {2018-06-01},

journal = {Physical Review B},

volume = {97},

number = {24},

pages = {245105},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{COOPER2018,

title = {RF atomic magnetometer array with over 40 dB interference suppression using electron spin resonance},

author = {Robert J Cooper and David W Prescott and Garrett J Lee and Karen L Sauer},

url = {http://www.sciencedirect.com/science/article/pii/S1090780718302118 https://linkinghub.elsevier.com/retrieve/pii/S1090780718302118},

doi = {10.1016/j.jmr.2018.08.007},

issn = {10907807},

year  = {2018},

date = {2018-08-01},

journal = {Journal of Magnetic Resonance},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zhang2018db,

title = {Tuning the Electronic and Photonic Properties of Monolayer MoS 2 via In Situ Rhenium Substitutional Doping},

author = {Kehao Zhang and Brian M Bersch and Jaydeep Joshi and Rafik Addou and Christopher R Cormier and Chenxi Zhang and Ke Xu and Natalie C Briggs and Ke Wang and Shruti Subramanian and Kyeongjae Cho and Susan Fullerton-Shirey and Robert M Wallace and Patrick M Vora and Joshua A Robinson},

url = {http://doi.wiley.com/10.1002/adfm.201706950},

doi = {10.1002/adfm.201706950},

issn = {1616301X},

year  = {2018},

date = {2018-04-01},

journal = {Advanced Functional Materials},

volume = {28},

number = {16},

pages = {1706950},

abstract = {textcopyright 2018 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim. Doping is a fundamental requirement for tuning and improving the properties of conventional semiconductors. Recent doping studies including niobium (Nb) doping of molybdenum disulfide (MoS 2 ) and tungsten (W) doping of molybdenum diselenide (MoSe 2 ) have suggested that substitutional doping may provide an efficient route to tune the doping type and suppress deep trap levels of 2D materials. To date, the impact of the doping on the structural, electronic, and photonic properties of in situ-doped monolayers remains unanswered due to challenges including strong film substrate charge transfer, and difficulty achieving doping concentrations greater than 0.3 at%. Here, in situ rhenium (Re) doping of synthetic monolayer MoS 2 with ≈1 at% Re is demonstrated. To limit substrate film charge transfer, r-plane sapphire is used. Electronic measurements demonstrate that 1 at% Re doping achieves nearly degenerate n-type doping, which agrees with density functional theory calculations. Moreover, low-temperature photoluminescence indicates a significant quench of the defect-bound emission when Re is introduced, which is attributed to the Mo-O bond and sulfur vacancies passivation and reduction in gap states due to the presence of Re. The work presented here demonstrates that Re doping of MoS 2 is a promising route toward electronic and photonic engineering of 2D materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zhang2018d,

title = {Tuning the Electronic and Photonic Properties of Monolayer MoS2 via In Situ Rhenium Substitutional Doping},

author = {Kehao Zhang and Brian M Bersch and Jaydeep Joshi and Rafik Addou and Christopher R Cormier and Chenxi Zhang and Ke Xu and Natalie C Briggs and Ke Wang and Shruti Subramanian and Kyeongjae Cho and Susan Fullerton-Shirey and Robert M Wallace and Patrick M Vora and Joshua A Robinson},

url = {http://doi.wiley.com/10.1002/adfm.201706950},

doi = {10.1002/adfm.201706950},

issn = {1616301X},

year  = {2018},

date = {2018-04-01},

journal = {Advanced Functional Materials},

volume = {28},

number = {16},

pages = {1706950},

abstract = {textcopyright 2018 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim. Doping is a fundamental requirement for tuning and improving the properties of conventional semiconductors. Recent doping studies including niobium (Nb) doping of molybdenum disulfide (MoS 2 ) and tungsten (W) doping of molybdenum diselenide (MoSe 2 ) have suggested that substitutional doping may provide an efficient route to tune the doping type and suppress deep trap levels of 2D materials. To date, the impact of the doping on the structural, electronic, and photonic properties of in situ-doped monolayers remains unanswered due to challenges including strong film substrate charge transfer, and difficulty achieving doping concentrations greater than 0.3 at%. Here, in situ rhenium (Re) doping of synthetic monolayer MoS 2 with ≈1 at% Re is demonstrated. To limit substrate film charge transfer, r-plane sapphire is used. Electronic measurements demonstrate that 1 at% Re doping achieves nearly degenerate n-type doping, which agrees with density functional theory calculations. Moreover, low-temperature photoluminescence indicates a significant quench of the defect-bound emission when Re is introduced, which is attributed to the Mo-O bond and sulfur vacancies passivation and reduction in gap states due to the presence of Re. The work presented here demonstrates that Re doping of MoS 2 is a promising route toward electronic and photonic engineering of 2D materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Keles2018,

title = {Weyl nodes in periodic structures of superconductors and spin-active materials},

author = {Ahmet Keles and Erhai Zhao},

url = {https://doi.org/10.1098/rsta.2015.0151 http://rsta.royalsocietypublishing.org/lookup/doi/10.1098/rsta.2015.0151},

doi = {10.1098/rsta.2015.0151},

issn = {1364-503X},

year  = {2018},

date = {2018-08-01},

journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},

volume = {376},

number = {2125},

pages = {20150151},

publisher = {The Royal Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kim2017c,

title = {A stretchable crumpled graphene photodetector with plasmonically enhanced photoresponsivity},

author = {Minsu Kim and Pilgyu Kang and Juyoung Leem and SungWoo Nam},

url = {http://xlink.rsc.org/?DOI=C6NR09338H},

doi = {10.1039/C6NR09338H},

issn = {2040-3364},

year  = {2017},

date = {2017-01-01},

journal = {Nanoscale},

volume = {9},

number = {12},

pages = {4058--4065},

abstract = {Graphene has been widely explored for flexible, high-performance photodetectors due to its exceptional mechanical strength, broadband absorption, and high carrier mobility. However, the low stretchability and limited photoabsorption of graphene have restricted its applications in flexible and highly sensitive photodetection systems. Various hybrid systems based on photonic or plasmonic nanostructures have been introduced to improve the limited photoresponsivity of graphene photodetectors. In most cases, the hybrid systems succeeded in the enhancement of photoresponsivity, but showed limited mechanical stretchability. Here, we demonstrate a stretchable photodetector based on a crumpled graphene\textendashgold nanoparticle (AuNP) hybrid structure with ∼1200% enhanced photoresponsivity, compared to a conventional flat graphene-only photodetector, and exceptional mechanical stretchability up to a 200% tensile strain. We achieve plasmonically enhanced photoresponsivity by integrating AuNPs with graphene. By crumpling the hybrid structure, we realize mechanical stretchability and further enhancement of the optical absorption by densification. We also demonstrate that our highly stretchable photodetector with enhanced photoresponsivity can be integrated on a contact lens and a spring structure. We believe that our stretchable, high performance graphene photodetector can find broad applications for conformable and flexible optical sensors and dynamic mechanical strain sensors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000412167800003,

title = {Corrosion testing of metals in contact with calcium chloride hexahydrate 

 used for thermal energy storage},

author = {S. J. Ren and J. Charles and X. C. Wang and F. X. Nie and C. Romero and S. Neti and Y. Zheng and S. Hoenig and C. Chen and F. Cao and R. Bonner and H. Pearlman},

doi = {10.1002/maco.201709432},

issn = {0947-5117},

year  = {2017},

date = {2017-10-01},

journal = {MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION},

volume = {68},

number = {10},

pages = {1046-1056},

publisher = {WILEY-V C H VERLAG GMBH},

address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY},

abstract = {Thermal energy storage (TES) using a phase change material (PCM) has 

 been proposed as a supplemental cooling system to improve the 

 performance of power plant air-cooled condensers (ACCs). In this 

 proposed system, frozen PCM would remove heat from plant's condensing 

 steam during the day, which would melt the PCM. The PCM would be frozen 

 at night as its stored heat is rejected to the cooler atmosphere. 

 Calcium chloride hexahydrate (CaCl2 center dot 6H(2)O) is an attractive 

 material to serve as a PCM in this innovative system due to its 

 appropriate melting temperature, low price, and relatively high latent 

 heat of fusion. The corrosion of container materials is a major 

 challenge in using CaCl2 center dot 6H(2)O. Any material used needs to 

 survive constant exposure to the salt for several years to ensure a long 

 operational life for the system. In this study, the corrosion behavior 

 of four metals in contact with CaCl2 center dot 6H(2)O was 

 experimentally investigated. Three different temperature conditions and 

 two pH level conditions were considered under static metal exposure 

 conditions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevA.95.063619,

title = {Effective theory of interacting fermions in shaken square optical lattices},

author = {Ahmet Kele\c{s} and Erhai Zhao and Vincent W Liu},

url = {https://link.aps.org/doi/10.1103/PhysRevA.95.063619 http://link.aps.org/doi/10.1103/PhysRevA.95.063619},

doi = {10.1103/PhysRevA.95.063619},

issn = {2469-9926},

year  = {2017},

date = {2017-06-01},

journal = {Physical Review A},

volume = {95},

number = {6},

pages = {063619},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevLett.119.050401,

title = {Frustrated Magnetism of Dipolar Molecules on a Square Optical Lattice: Prediction of a Quantum Paramagnetic Ground State},

author = {Haiyuan Zou and Erhai Zhao and Vincent W Liu},

url = {https://link.aps.org/doi/10.1103/PhysRevLett.119.050401 http://link.aps.org/doi/10.1103/PhysRevLett.119.050401},

doi = {10.1103/PhysRevLett.119.050401},

issn = {0031-9007},

year  = {2017},

date = {2017-07-01},

journal = {Physical Review Letters},

volume = {119},

number = {5},

pages = {050401},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wang2017e,

title = {Mechanical instability driven self-assembly and architecturing of 2D materials},

author = {Michael Cai Wang and Juyoung Leem and Pilgyu Kang and Jonghyun Choi and Peter Knapp and Keong Yong and SungWoo Nam},

url = {http://stacks.iop.org/2053-1583/4/i=2/a=022002?key=crossref.f4723d0c820bc3cf2650ad83fec550c1},

doi = {10.1088/2053-1583/aa62e8},

issn = {2053-1583},

year  = {2017},

date = {2017-03-01},

journal = {2D Materials},

volume = {4},

number = {2},

pages = {022002},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Guterding2017_PRL_Nontrivial,

title = {Nontrivial Role of Interlayer Cation States in Iron-Based Superconductors},

author = {Daniel Guterding and Harald O Jeschke and I I Mazin and J K Glasbrenner and E Bascones and Roser Valent\'{i}},

url = {https://link.aps.org/doi/10.1103/PhysRevLett.118.017204},

doi = {10.1103/PhysRevLett.118.017204},

issn = {0031-9007},

year  = {2017},

date = {2017-01-01},

journal = {Physical Review Letters},

volume = {118},

number = {1},

pages = {017204},

publisher = {American Physical Society},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Oliver2017b,

title = {The structural phases and vibrational properties of Mo 1−x W x Te 2 alloys},

author = {Sean M Oliver and Ryan Beams and Sergiy Krylyuk and Irina Kalish and Arunima K Singh and Alina Bruma and Francesca Tavazza and Jaydeep Joshi and Iris R Stone and Stephan J Stranick and Albert V Davydov and Patrick M Vora},

url = {http://arxiv.org/abs/1703.10985%0Ahttp://dx.doi.org/10.1088/2053-1583/aa7a32 http://stacks.iop.org/2053-1583/4/i=4/a=045008?key=crossref.6ba8b9b9212ad2239ec721d728eec57f},

doi = {10.1088/2053-1583/aa7a32},

issn = {2053-1583},

year  = {2017},

date = {2017-08-01},

journal = {2D Materials},

volume = {4},

number = {4},

pages = {045008},

publisher = {IOP Publishing},

abstract = {The structural polymorphism in transition metal dichalcogenides (TMDs) provides exciting opportunities for developing advanced electronics. For example, MoTe$_2$ crystallizes in the 2H semiconducting phase at ambient temperature and pressure, but transitions into the 1T$^backslashprime$ semimetallic phase at high temperatures. Alloying MoTe$_2$ with WTe$_2$ reduces the energy barrier between these two phases, while also allowing access to the T$_d$ Weyl semimetal phase. The MoWTe$_2$ alloy system is therefore promising for developing phase change memory technology. However, achieving this goal necessitates a detailed understanding of the phase composition in the MoTe$_2$-WTe$_2$ system. We combine polarization-resolved Raman spectroscopy with X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM) to study MoWTe$_2$ alloys over the full compositional range x from 0 to 1. We identify Raman and XRD signatures characteristic of the 2H, 1T$^backslashprime$, and T$_d$ structural phases that agree with density-functional theory (DFT) calculations, and use them to identify phase fields in the MoTe$_2$-WTe$_2$ system, including single-phase 2H, 1T$^backslashprime$, and T$_d$ regions, as well as a two-phase 1T$^backslashprime$ + T$_d$ region. Disorder arising from compositional fluctuations in MoWTe$_2$ alloys breaks inversion and translational symmetry, leading to the activation of an infrared 1T$^backslashprime$-MoTe$_2$ mode and the enhancement of a double-resonance Raman process in 2H-MoWTe$_2$ alloys. Compositional fluctuations limit the phonon correlation length, which we estimate by fitting the observed asymmetric Raman lineshapes with a phonon confinement model. These observations reveal the important role of disorder in MoWTe$_2$ alloys, clarify the structural phase boundaries, and provide a foundation for future explorations of phase transitions and electronic phenomena in this system.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000364037600001,

title = {Probing Nanoscale Thermal Transport in Surfactant Solutions},

author = {Fangyu Cao and Ying Liu and Jiajun Xu and Yadong He and B. Hammouda and Rui Qiao and Bao Yang},

doi = {10.1038/srep16040},

issn = {2045-2322},

year  = {2015},

date = {2015-11-01},

journal = {SCIENTIFIC REPORTS},

volume = {5},

publisher = {NATURE PUBLISHING GROUP},

address = {MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND},

abstract = {Surfactant solutions typically feature tunable nanoscale, internal 

 structures. Although rarely utilized, they can be a powerful platform 

 for probing thermal transport in nanoscale domains and across interfaces 

 with nanometer-size radius. Here, we examine the structure and thermal 

 transport in solution of AOT (Dioctyl sodium sulfosuccinate) in n-octane 

 liquids using small-angle neutron scattering, thermal conductivity 

 measurements, and molecular dynamics simulations. We report the first 

 experimental observation of a minimum thermal conductivity occurring at 

 the critical micelle concentration (CMC): the thermal conductivity of 

 the surfactant solution decreases as AOT is added till the onset of 

 micellization but increases as more AOT is added. The decrease of 

 thermal conductivity with AOT loading in solutions in which AOT 

 molecules are dispersed as monomers suggests that even the interfaces 

 between individual oleophobic headgroup of AOT molecules and their 

 surrounding non-polar octane molecules can hinder heat transfer. The 

 increase of thermal conductivity with AOT loading after the onset of 

 micellization indicates that the thermal transport in the core of AOT 

 micelles and across the surfactant-oil interfaces, both of which span 

 only a few nanometers, are efficient.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}