papers

Publications (224)

cond-mat.mes-hall2015

Drumhead Surface States and Topological Nodal-Line Fermions in TlTaSe2

Guang Bian, Tay-Rong Chang, Hao Zheng +13

A topological nodal-line semimetal is a new condensed matter state with one-dimensional bulk nodal lines and two-dimensional drumhead surface bands. Based on first-principles calcu…

quant-ph2023

A Gell-Mann & Low Theorem Perspective on Quantum Computing: New Paradigm for Designing Quantum Algorithm

Chun-Tse Li, T. Tzen Ong, Lucas Wang +3

The Gell-Mann & Low theorem is a cornerstone of Quantum Field Theory (QFT) and condensed matter physics, and many-body perturbation theory is a foundational tool for treating inter…

cond-mat.mes-hall2025

Surface-dominant transport in Weyl semimetal NbAs nanowires for next-generation interconnects

Yeryun Cheon, Mehrdad T. Kiani, Yi-Hsin Tu +20

Ongoing demands for smaller and more energy efficient electronic devices necessitate alternative interconnect materials with lower electrical resistivity at reduced dimensions. Des…

cond-mat.mtrl-sci2020

Noncollinear Magnetic Modulation of Weyl Nodes in Ferrimagnetic MnGa

Cheng-Yi Huang, Hugo Aramberri, Hsin Lin +1

The tetragonal ferrimagnetic MnGa exhibits a wide range of intriguing magnetic properties. Here, we report the emergence of topologically nontrivial nodal lines in the absence…

cond-mat.mes-hall2014

Topological phase transition and quantum spin Hall state in TlBiS

Bahadur Singh, Hsin Lin, R. Prasad +1

We have investigated the bulk and surface electronic structures and band topology of TlBiS as a function of strain and electric field using \textit{ab-initio} calculations. In…

cond-mat.mtrl-sci2025

Strain-Induced Charge Density Waves with Emergent Topological States in Monolayer NbSe2

Wei-Chi Chiu, Sougata Mardanya, Robert Markiewicz +7

Emergence of topological states in strongly correlated systems, particularly two-dimensional (2D) transition-metal dichalcogenides, offers a platform for manipulating electronic pr…

cond-mat.mes-hall2020

Dimensionality-dependent type-II Weyl semimetal state in MoWTe

Peiling Li, Ya Deng, Chuanghan Hsu +15

Weyl nodes and Fermi arcs in type-II Weyl semimetals (WSMs) have led to lots of exotic transport phenomena. Recently, MoWTe has been established as a type-I…

cond-mat.mes-hall2019

Topological photocurrent responses from chiral surface Fermi arcs

Guoqing Chang, Jiaxin Yin, Titus Neupert +10

The nonlinear optical responses from topological semimetals are crucial in both understanding the fundamental properties of quantum materials and designing next-generation light-se…

cond-mat.str-el2012

Coexisting pseudogap, charge transfer gap, and Mott gap energy scales in the resonant inelastic x-ray scattering spectra of electron-doped cuprates

Susmita Basak, Tanmoy Das, Hsin Lin +3

We present a computation of Cu K-edge resonant inelastic x-ray scattering (RIXS) spectra for electron-doped cuprates which includes coupling to bosonic fluctuations. Comparison wit…

cond-mat.str-el2020

Field-induced Metal-Insulator Transition in -EuP

Guangqiang Wang, Guoqing Chang, Huibin Zhou +5

Metal-insulator transition (MIT) is one of the most conspicuous phenomena in correlated electron systems. However such transition has rarely been induced by an external magnetic fi…

cond-mat.str-el2013

Mapping the unconventional orbital texture in topological crystalline insulators

Ilija Zeljkovic, Yoshinori Okada, Cheng-Yi Huang +11

The newly discovered topological crystalline insulators (TCIs) harbor a complex band structure involving multiple Dirac cones. These materials are potentially highly tunable by ext…

cond-mat.str-el2022

Evidence for electronic signature of magnetic transition in topological magnet HoSbTe

Nana Shumiya, Jia-Xin Yin, Guoqing Chang +11

Topological insulators with intrinsic magnetic order are emerging as an exciting platform to realize fundamentally new excitations from topological quantum states of matter. To stu…

cond-mat.mtrl-sci2015

Theoretical Discovery/Prediction: Weyl Semimetal states in the TaAs material (TaAs, NbAs, NbP, TaP) class

Shin-Ming Huang, Su-Yang Xu, Ilya Belopolski +9

The recent discoveries of Dirac fermions in graphene and on the surface of topological insulators have ignited worldwide interest in physics and materials science. A Weyl semimetal…

cond-mat.mtrl-sci2023

Feature-energy duality of topological boundary states in multilayer quantum spin Hall insulator

Yueh-Ting Yao, Xiaoting Zhou, Yi-Chun Hung +3

Gapless topological boundary states characterize nontrivial topological phases arising from the bulk-boundary correspondence in symmetry-protected topological materials, such as th…

cond-mat.mes-hall2023

Time-Reversal Soliton Pairs In Even Spin-Chern-Number Higher-Order Topological Insulators

Yi-Chun Hung, Baokai Wang, Chen-Hsuan Hsu +2

Solitons formed through the one-dimensional mass-kink mechanism on the edges of two-dimensional systems with non-trivial topology play an important role in the emergence of higher-…

cond-mat.supr-con2019

Vector field controlled vortex lattice symmetry in LiFeAs

Songtian S. Zhang, Jia-Xin Yin, Guangyang Dai +8

We utilize a combination of vector magnetic field and scanning tunneling microscopy to elucidate the 3D field-based electronic phase diagram of a correlated iron-based superconduct…

cond-mat.mtrl-sci2017

Observation of Effective Pseudospin Scattering in ZrSiS

Michael S. Lodge, Guoqing Chang, Cheng-Yi Huang +10

3D Dirac semimetals are an emerging class of materials that possess topological electronic states with a Dirac dispersion in their bulk. In nodal-line Dirac semimetals, the conduct…

cond-mat.mtrl-sci2016

Discovery of a new type of topological Weyl fermion semimetal state in MoWTe

Ilya Belopolski, Daniel S. Sanchez, Yukiaki Ishida +23

The recent discovery of a Weyl semimetal in TaAs offers the first Weyl fermion observed in nature and dramatically broadens the classification of topological phases. However, in Ta…

cond-mat.str-el2021

Realization of an intrinsic, ferromagnetic topological state in MnBi8Te13

Chaowei Hu, Lei Ding, Kyle N. Gordon +18

The interplay between topology and magnetism is essential for realizing novel topological states including the axion insulator, the magnetic Weyl semimetal, etc. An intrinsically f…

cond-mat.mes-hall2014

Dirac mass generation from crystal symmetry breaking on the surfaces of topological crystalline insulators

Ilija Zeljkovic, Yoshinori Okada, Maksym Serbyn +12

The tunability of topological surface states (SS) and controllable opening of the Dirac gap are of fundamental and practical interest in the field of topological materials. In topo…

cond-mat.supr-con2022

Multi-Band Superconductivity in Strongly Hybridized 1T'-WTe/NbSe Heterostructures

Wei Tao, Zheng Jue Tong, Anirban Das +11

The interplay of topology and superconductivity has become a subject of intense research in condensed matter physics for the pursuit of topologically non-trivial forms of supercond…

cond-mat.mes-hall2015

Fermi arc topology and interconnectivity in Weyl fermion semimetals TaAs, TaP, NbAs, and NbP

Chi-Cheng Lee, Su-Yang Xu, Shin-Ming Huang +11

The family of binary compounds including TaAs, TaP, NbAs, and NbP was recently discovered as the first realization of Weyl semimetals. In order to develop a comprehensive descripti…

cond-mat.mtrl-sci2015

Nanoscale Determination of the Mass Enhancement Factor in the Lightly-Doped Bulk Insulator Lead Selenide

Ilija Zeljkovic, Kane L Scipioni, Daniel Walkup +10

Bismuth chalcogenides and lead telluride/selenide alloys exhibit exceptional thermoelectric properties which could be harnessed for power generation and device applications. Since…

cond-mat.mes-hall2015

Hedgehog spin texture and competing orders associated with strains on the surface of a topological crystalline insulator

Cheng-Yi Huang, Hsin Lin, Yung Jui Wang +2

We have investigated spin reorientation phenomena and interaction driven effects under the presence of applied strains on the (001) surface of PbSn(Te, Se) topological…

cond-mat.mes-hall2016

Interplay of orbital effects and nanoscale strain in topological crystalline insulators

Daniel Walkup, Badih Assaf, Kane L Scipioni +6

Orbital degrees of freedom can have pronounced effects on the fundamental properties of electrons in solids. In addition to influencing bandwidths, gaps, correlation strength and d…

cond-mat.mes-hall2012

Magnetically induced spin reorientation on the surface of a topological insulator (a surface magnetic topological insulator MBE film)

Su-Yang Xu, M. Neupane, Chang Liu +18

The surface of topological insulators is proposed as a promising platform for spintronics and quantum information applications. In particular, when time- reversal symmetry is broke…

cond-mat.mtrl-sci2025

Visualizing higher-fold topology in chiral crystals

Tyler A Cochran, Ilya Belopolski, Kaustuv Manna +21

Novel topological phases of matter are fruitful platforms for the discovery of unconventional electromagnetic phenomena. Higher-fold topology is one example, where the low-energy d…

cond-mat.str-el2026

Scaling universal Fermi network toward ground states: A diffusion-Monte-Carlo assessment

Yu-Sheng Li, Saskia Poldmaa, Tzen Ong +4

In this work, we show that Fermi Sets---a provably universal neural network architecture for fermionic wavefunctions---can be systematically scaled up to find interacting ground st…

cond-mat.supr-con2023

Doubling of the superconducting transition temperature in ultra-clean wafer-scale aluminum nanofilms

Ching-Chen Yeh, Thi-Hien Do, Pin-Chi Liao +12

Superconducting properties of thin films can be vastly different from those of bulk materials. Seminal work has shown the critical temperature Tc of elemental superconductors decre…

cond-mat.mes-hall2019

Spin-dependent scattering induced negative magnetoresistance in topological insulator Bi2Te3 nanowires

Biplab Bhattacharyya, Bahadur Singh, R. P. Aloysius +7

Studies of negative magnetoresistance in novel materials have recently been in the forefront of spintronic research. Here, we report an experimental observation of the temperature…

cond-mat.mtrl-sci2025

Emergent spin Hall quantization and high-order van Hove singularities in square-octagonal MAZ

Rahul Verma, Yash Vardhan, Hsin Lin +1

Quantum spin Hall (QSH) insulators are versatile platforms for exploring exotic quantum phases, especially when combined with high-order van Hove singularities (VHSs) that enhance…

cond-mat.mes-hall2015

Discovery of a Weyl Fermion semimetal state in NbAs

Su-Yang Xu, Nasser Alidoust, Ilya Belopolski +21

We report the discovery of Weyl semimetal NbAs featuring topological Fermi arc surface states.

cond-mat.mtrl-sci2009

Role of Oxygen Electrons in the Metal-Insulator Transition in the Magnetoresistive Oxide LaSrMnO Probed by Compton Scattering

B. Barbiellini, A. Koizumi, P. E. Mijnarends +7

We have studied the [100]-[110] anisotropy of the Compton profile in the bilayer manganite. Quantitative agreement is found between theory and experiment with respect to the anisot…

cond-mat.mtrl-sci2018

Searching for topological Fermi arcs via quasiparticle interference on a type-II Weyl semimetal MoTe

Davide Iaia, Guoqing Chang, Tay-Rong Chang +5

Weyl semimetals display a novel topological phase of matter where the Weyl nodes emerge in pairs of opposite chirality and can be seen as either a source or a sink of Berry curvatu…

cond-mat.mes-hall2025

Observation of the Axion quasiparticle in 2D MnBiTe

Jian-Xiang Qiu, Barun Ghosh, Jan Schütte-Engel +32

In 1978, Wilczek and Weinberg theoretically discovered a new boson-the Axion-which is the coherent oscillation of the field in QCD. Its existence can solve multiple fundamenta…

cond-mat.mtrl-sci2019

Nonlinear magnetotransport shaped by Fermi surface topology and convexity in WTe2

Pan He, Chuang-Han Hsu, Shuyuan Shi +7

The nature of Fermi surface defines the physical properties of conductors and many physical phenomena can be traced to its shape. Although the recent discovery of a current-depende…

cond-mat.mtrl-sci2017

A novel artificial condensed matter lattice and a new platform for one-dimensional topological phases

Ilya Belopolski, Su-Yang Xu, Nikesh Koirala +22

Engineered lattices in condensed matter physics, such as cold atom optical lattices or photonic crystals, can have fundamentally different properties from naturally-occurring elect…

cond-mat.supr-con2023

Unconventional superconducting pairing in a B20 Kramers Weyl semimetal

Sougata Mardanya, Mehdi Kargarian, Rahul Verma +6

Topological superconductors present an ideal platform for exploring nontrivial superconductivity and realizing Majorana boundary modes in materials. However, finding a single-phase…

cond-mat.mtrl-sci2015

Atomic Scale Visualization of Quantum Interference on a Weyl Semimetal Surface by Scanning Tunneling Microscopy/Spectroscopy

Hao Zheng, Su-Yang Xu, Guang Bian +19

Weyl semimetals may open a new era in condensed matter physics, materials science and nanotech after graphene and topological insulators. We report the first atomic scale view of t…

cond-mat.mes-hall2015

Surface Versus Bulk Dirac States Tuning in a Three-Dimensional Topological Dirac Semimetal

Madhab Neupane, Su-Yang Xu, Nasser Alidoust +13

Recently, crystalline-symmetry-protected three-dimensional (3D) bulk Dirac semimetal phase has been experimentally identified in a stoichiometric high-mobility compound, Cd3As2. Th…

cond-mat.str-el2014

Nanoscale interplay of strain and doping in a high-temperature superconductor

Ilija Zeljkovic, Jouko Nieminen, Dennis Huang +10

The highest temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable which could be harnessed to enhance the supe…

cond-mat.str-el2025

Observation of charge density wave excitonic order parameter in topological insulator monolayer WTe2

Liam Watson, Joan Ripoll, Zhengjue Tong +12

Strong electron-hole interactions in a semimetal or narrow-gap semiconductor may drive a ground state of condensed excitons. Monolayer WTe2 has been proposed as a host material for…

cond-mat.mtrl-sci2023

Feature Spectrum Topology

Baokai Wang, Yi-Chun Hung, Xiaoting Zhou +2

Topology is a fundamental aspect of quantum physics, and it has led to key breakthroughs and results in various fields of quantum materials. In condensed matters, this has culminat…

cond-mat.mes-hall2015

Topological Nodal-Line Fermions in the Non-Centrosymmetric Superconductor Compound PbTaSe2

Guang Bian, Tay-Rong Chang, Raman Sankar +18

We report the identification of a Topological Nodal-Line Semimetal state in PbTaSe2.

cond-mat.mes-hall2013

Topological phase transition and two dimensional topological insulators in Ge-based thin films

Bahadur Singh, Hsin Lin, R. Prasad +1

We discuss possible topological phase transitions in Ge-based thin films of Ge(BiSb)Te as a function of layer thickness and Bi concentration using the first…

cond-mat.mes-hall2013

Reversal of the circular dichroism in the angle-resolved photoemission from Bi2Te3

M. R. Scholz, J. Sánchez-Barriga, J. Braun +11

The helical Dirac fermions at the surface of topological insulators show a strong circular dichroism which has been explained as being due to either the initial-state spin angular…

cond-mat.mes-hall2018

Topological quantum properties of chiral crystals

Guoqing Chang, Benjamin J. Wieder, Frank Schindler +10

Chiral crystals are materials whose lattice structure has a well-defined handedness due to the lack of inversion, mirror, or other roto-inversion symmetries. These crystals represe…

cond-mat.mtrl-sci2019

Transition from Intrinsic to Extrinsic Anomalous Hall Effect in the Ferromagnetic Weyl Semimetal PrAlGeSi

Hung-Yu Yang, Bahadur Singh, Baozhu Lu +10

Recent reports of a large anomalous Hall effect (AHE) in ferromagnetic Weyl semimetals (FM WSM) have led to a resurgence of interest in this enigmatic phenomenon. However, due to a…

cond-mat.mtrl-sci2021

Aspects of symmetry and topology in the charge density wave phase of 1T-TiSe2

Shin-Ming Huang, Su-Yang Xu, Bahadur Singh +5

The charge density wave (CDW) in 1T-TiSe2 accompanied by the periodic lattice distortion has a nontrivial symmetry configuration. The symmetry is important as an indication of the…

cond-mat.mes-hall2011

Novel Spin-texture on the warped Dirac-cone surface states in topological insulators

Susmita Basak, Hsin Lin, L. A. Wray +4

We have investigated the nature of surface states in the Bi2Te3 family of three-dimensional topological insulators using first-principles calculations as well as model Hamiltonians…

cond-mat.str-el2017

Magnetic tunneling induced Weyl node annihilation in TaP

Cheng-Long Zhang, Su-Yang Xu, C. M. Wang +20

Weyl nodes are topological objects in three-dimensional metals. Their topological property can be revealed by studying the high-field transport properties of a Weyl semimetal. Whil…

cond-mat.mtrl-sci2017

Ultraquantum magnetoresistance in Kramers Weyl semimetal candidate -Ag2Se

Cheng-Long Zhang, Frank Schindler, Haiwen Liu +14

The topological semimetal -Ag2Se features a Kramers Weyl node at the origin in momentum space and a quadruplet of spinless Weyl nodes, which are annihilated by spin-orbit coupl…

cond-mat.mtrl-sci2017

Band Topology and Dichroic Signature of Bismuth

Guang Bian, Tay-Rong Chang, Xiaoxiong Wang +3

Bismuth has been the key element in the discovery and development of topological insulator materials. Previous theoretical studies indicated that Bi is topologically trivial and it…

cond-mat.mtrl-sci2013

Adiabatic transformation as a search tool for new topological insulators: distorted ternary LiAgSb-class semiconductors and related compounds

Hsin Lin, Tanmoy Das, Yung Jui Wang +4

We demonstrate that first-principles based adiabatic continuation approach is a very powerful and efficient tool for constructing topological phase diagrams and locating non-trivia…

cond-mat.mes-hall2015

Experimental Observation of Two Massless Dirac-Fermion Gases in Graphene-Topological Insulator Heterostructure

Guang Bian, Ting-Fung Chung, Chang Liu +19

Graphene and topological insulators (TI) possess two-dimensional Dirac fermions with distinct physical properties. Integrating these two Dirac materials in a single device creates…

cond-mat.mes-hall2015

Topological semimetals and topological insulators in rare earth monopnictides

Minggang Zeng, Chen Fang, Guoqing Chang +5

We use first principles calculations to study the electronic properties of rock salt rare earth monopnictides La (N, P, As, Sb, Bi). A new type of topological band crossing…

cond-mat.mtrl-sci2012

Topological Crystalline Insulators in the SnTe Material Class

Timothy H. Hsieh, Hsin Lin, Junwei Liu +3

Topological crystalline insulators are new states of matter in which the topological nature of electronic structures arises from crystal symmetries. Here we predict the first mater…

cond-mat.supr-con2010

Uniaxial "nematic-like" electronic structure and Fermi surface of untwinned CaFe2As2

Qiang Wang, Zhe Sun, Eli Rotenberg +8

Obtaining the electronic structure of the newly discovered iron-based superconductors is the key to understanding the mechanism of their high-temperature superconductivity. We used…

cond-mat.str-el2005

One-band tight-binding model parametrization of the high- cuprates, including the effect of -dispersion

R. S. Markiewicz, S. Sahrakorpi, M. Lindroos +2

We discuss the effects of interlayer hopping and the resulting -dispersion in the cuprates within the framework of the one-band tight binding (TB) model Hamiltonian. Specific…

cond-mat.str-el2006

Effect of Hole Doping on the Electronic Structure of Tl2201

S. Sahrakorpi, Hsin Lin, R. S. Markiewicz +1

We discuss doping dependencies of the electronic structure and Fermi surface of the monolayer TlCuBaCuO (Tl2201). The TlO bands are found to be particularl…

cond-mat.mtrl-sci2016

Topological Weyl phase transition in MoWTe

Ilya Belopolski, Daniel S. Sanchez, Yukiaki Ishida +21

Topological phases of matter exhibit phase transitions between distinct topological classes. These phase transitions are exotic in that they do not fall within the traditional Ginz…

cond-mat.mtrl-sci2021

Layer Hall effect in a 2D topological Axion antiferromagnet

Anyuan Gao, Yu-Fei Liu, Chaowei Hu +33

While ferromagnets have been known and exploited for millennia, antiferromagnets (AFMs) were only discovered in the 1930s. The elusive nature indicates AFMs' unique properties: At…

cond-mat.mtrl-sci2025

Probing the semiconductor-to-dirac semimetal transition in Na-Sb-Bi alloys with x-ray Compton scattering

Aki Pulkkinen, Veenavee Nipunika Kothalawala, Kosuke Suzuki +12

We discuss electron redistribution during the semiconductor-to-Dirac semimetal transition in Na-Sb-Bi alloys using x-ray Compton scattering experiments combined with first-principl…

cond-mat.mes-hall2019

Termination Dependent Topological Surface States in Nodal Loop Semimetal HfP2

Christopher Sims, M. Mofazzel Hosen, Hugo Aramberri +11

Symmetry plays a major role in all disciplines of physics. Within the field of topological materials there is a great interest in understanding how the mechanics of crystalline and…

cond-mat.mes-hall2019

Temperature Dependent Electronic Structure in a Higher Order Topological Insulator Candidate EuInAs

Sabin Regmi, Md Mofazzel Hosen, Barun Ghosh +12

The higher order topological insulator (HOTI) has enticed enormous research interests owing to its novelty in supporting gapless states along the hinges of the crystal. Despite sev…

cond-mat.mes-hall2020

Exceptionally large anomalous Hall effect due to anticrossing of spin-split bands in the antiferromagnetic half-Heusler compound TbPtBi

Yanglin Zhu, Bahadur Singh, Yu Wang +9

We have investigated magnetotransport properties and the topological electronic structure of the half-Heusler compound TbPtBi. Our experiments reveal an exceptionally large anomalo…

cond-mat.mes-hall2021

A Higher-Order Topological Insulator Phase in a Modulated Haldane Model

Baokai Wang, Xiaoting Zhou, Hsin Lin +1

We explore topological properties of a modulated Haldane model (MHM) in which the strength of the nearest-neighbor and next-nearest-neighbor terms is made unequal and the three-fol…

cond-mat.mes-hall2016

Measuring Chern numbers above the Fermi level in the Type II Weyl semimetal MoWTe

Ilya Belopolski, Su-Yang Xu, Yukiaki Ishida +30

It has recently been proposed that electronic band structures in crystals give rise to a previously overlooked type of Weyl fermion, which violates Lorentz invariance and, conseque…

cond-mat.str-el2017

Atomic-scale visualization of surface-assisted orbital order

Howon Kim, Yasuo Yoshida, Chi-Cheng Lee +6

Orbital-related physics attracts growing interest in condensed matter research, but direct real-space access of the orbital degree of freedom is challenging. Here we report a first…

cond-mat.mtrl-sci2014

Direct observation of the transition from indirect to direct bandgap in atomically thin epitaxial MoSe2

Yi Zhang, Tay-Rong Chang, Bo Zhou +13

Quantum systems in confined geometries are host to novel physical phenomena. Examples include quantum Hall systems in semiconductors and Dirac electrons in graphene. Interest in su…

cond-mat.mes-hall2023

Quantized Hall current in topological nodal-line semimetal

Po-Hsin Shih, Thi-Nga Do, Godfrey Gumbs +3

Photocurrent acts as one of measurable responses of material to light, which has proved itself to be crucial for sensing and energy harvesting. Topological semimetals with gapless…

cond-mat.mes-hall2024

Topological Orbital Hall Effect

Baokai Wang, Yi-Chun Hung, Hsin Lin +3

The orbital Hall effect (OHE) is attracting recent interest due to its fundamental science implications and potential applications in orbitronics and spintronics. Unlike the spin H…

cond-mat.mtrl-sci2022

Collective plasmonic modes in the chiral multifold fermionic material CoSi

Debasis Dutta, Barun Ghosh, Bahadur Singh +4

Plasmonics in topological semimetals offers exciting opportunities for fundamental physics exploration as well as for technological applications. Here, we investigate plasmons in t…

cond-mat.str-el2025

Direct Visualization of a Disorder Driven Electronic Smectic Phase in Nonsymmorphic Square-Net Semimetal GdSbTe

Balaji Venkatesan, Syu-You Guan, Jen-Te Chang +14

Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pn…

cond-mat.mtrl-sci2020

Discovery of a quantum limit Chern magnet TbMn6Sn6

Jia-Xin Yin, Wenlong Ma, Tyler A. Cochran +23

The quantum level interplay between geometry, topology, and correlation is at the forefront of fundamental physics. Owing to the unusual lattice geometry and breaking of time-rever…

cond-mat.mtrl-sci2020

Topological Dirac Semimetal Phase in Bismuth Based Anode Materials for Sodium-Ion Batteries

Wei-Chi Chiu, Bahadur Singh, Sougata Mardanya +7

Bismuth has recently attracted interest in connection with Na-ion battery anodes due to its high volumetric capacity. It reacts with Na to form NaBi which is a prototypical Dir…

cond-mat.mes-hall2017

Mirror protected Dirac fermions on a Weyl semimetal NbP surface

Hao Zheng, Guoqing Chang, Shin-Ming Huang +15

The first Weyl semimetal was recently discovered in the NbP class of compounds. Although the topology of these novel materials has been identified, the surface properties are not y…

cond-mat.mes-hall2012

Hedgehog Spin-texture and Berry's Phase tuning in a Magnetic Topological Insulator

Su-Yang Xu, Madhab Neupane, Chang Liu +18

Understanding and control of spin degrees of freedom on the surfaces of topological materials are key to future applications as well as for realizing novel physics such as the axio…

cond-mat.mes-hall2018

Non-saturating Quantum Magnetization in Weyl semimetal TaAs

Cheng-Long Zhang, C. M. Wang, Zhujun Yuan +8

Detecting the spectroscopic signatures of Dirac-like quasiparticles in emergent topological materials is crucial for searching their potential applications. Magnetometry is a power…

cond-mat.mtrl-sci2015

Unoccupied electronic structure and signatures of topological Fermi arcs in the Weyl semimetal candidate MoWTe

Ilya Belopolski, Su-Yang Xu, Yukiaki Ishida +30

Weyl semimetals have sparked intense research interest, but experimental work has been limited to the TaAs family of compounds. Recently, a number of theoretical works have predict…

cond-mat.mes-hall2014

Observation of Quantum-Tunneling Modulated Spin Texture in Ultrathin Topological Insulator Bi2Se3 Films

Madhab Neupane, Anthony Richardella, Jaime Sánchez-Barriga +18

Understanding the spin-texture behavior of boundary modes in ultrathin topological insulator films is critically essential for the design and fabrication of functional nano-devices…

cond-mat.mes-hall2015

Unconventional transformation of spin Dirac phase across a topological quantum phase transition

Su-Yang Xu, Madhab Neupane, Ilya Belopolski +15

The topology of a topological material can be encoded in its surface states. These surface states can only be removed by a bulk topological quantum phase transition into a trivial…

cond-mat.mes-hall2016

Role of surface termination in realizing well-isolated topological surface states within the bulk band gap in TlBiSe and TlBiTe

Bahadur Singh, Hsin Lin, R. Prasad +1

Electronic structures associated with the flat (polar) Se/Te- or Tl-terminated surfaces of TlBiSe and TlBiTe are predicted to harbor not only Dirac cone states, but also tr…

cond-mat.str-el2016

3D Dirac cone carrier dynamics in Na3Bi and Cd3As2

G. S. Jenkins, C. Lane, B. Barbiellini +12

Optical measurements and band structure calculations are reported on 3D Dirac materials. The electronic properties associated with the Dirac cone are identified in the reflectivity…

cond-mat.mtrl-sci2019

Purely rotational symmetry-protected topological crystalline insulator -Bi4Br4

Chuang-Han Hsu, Xiaoting Zhou, Qiong Ma +7

Recent theoretical advances have proposed a new class of topological crystalline insulator (TCI) phases protected by rotational symmetries. Distinct from topological insulators (TI…

cond-mat.supr-con2019

CuIr2Te4: A Quasi-Two-Dimensional Ternary Telluride Chalcogenide Superconductor

Dong Yan, Yijie Zeng, Guohua Wang +9

Here we report the first observation of superconductivity in the AB2X4-type ternary telluride CuIr2Te4, which is synthesized by a solid-state method in an evacuated quartz jacket.…

cond-mat.mes-hall2023

Real Space Characterization of Nonlinear Hall Effect in Confined Directions

Sheng Luo, Chuang-Han Hsu, Guoqing Chang +3

The nonlinear Hall effect (NLHE) is a phenomenon which could produce a transverse Hall voltage in a time-reversal-invariant material. Here, we report the real space characterizatio…

cond-mat.mes-hall2026

Nested Feature Spectrum Topology: Tripartite Topological Equivalence of Feature, Entanglement, and Wilson Loop Spectrum

Yi-Chun Hung, T. Tzen Ong, Hsin Lin

Topological phases of matter are traditionally characterized through symmetry-based classifications. In cases of symmetry breaking, the projected spectrum - obtained by projecting…

cond-mat.mes-hall2018

Discovery of topological chiral crystals with helicoid arc states

Daniel S. Sanchez, Ilya Belopolski, Tyler A. Cochran +19

The quantum behaviour of electrons in materials lays the foundation for modern electronic and information technology. Quantum materials with novel electronic and optical properties…

physics.optics2024

Origin of nonlinear photocurrents in chiral multifold semimetal CoSi unveiled by terahertz emission spectroscopy

Yao-Jui Chan, Syed Mohammed Faizanuddin, Raju Kalaivanan +8

Spectroscopic identification of distinct nonlinear photocurrents unveils quantum geometric properties of electron wavefunctions and the momentum-space topological structures. This…

cond-mat.mes-hall2015

A new type of Weyl semimetal with quadratic double Weyl fermions in SrSi2

Shin-Ming Huang, Su-Yang Xu, Ilya Belopolski +11

We identify a Weyl semimetal state in an inversion breaking, stoichiometric compound strontium silicide, SrSi, with many new and novel properties that are distinct from the TaA…

cond-mat.mtrl-sci2020

Discovery of topological Weyl fermion lines and drumhead surface states in a room temperature magnet

Ilya Belopolski, Kaustuv Manna, Daniel S. Sanchez +20

Topological matter is known to exhibit unconventional surface states and anomalous transport owing to unusual bulk electronic topology. In this study, we use photoemission spectros…

cond-mat.mes-hall2018

Topological Hourglass Dirac Semimetal in the Nonpolar Phase of AgBiO

Bahadur Singh, Barun Ghosh, Chenliang Su +3

Materials with tunable charge and lattice degrees of freedom provide excellent platforms for investigating multiple phases that can be controlled via external stimuli. We show how…

cond-mat.mes-hall2021

Topological Semimetals for Scaled Back-End-Of-Line Interconnect Beyond Cu

Ching-Tzu Chen, Utkarsh Bajpai, Nicholas A. Lanzillo +3

The resistance bottleneck in metal-interconnect scaling calls for new interconnect materials. This paper explores topological semimetals as a potential solution. After reviewing th…

cond-mat.mtrl-sci2021

A new noncollinear ferromagnetic Weyl semimetal with anisotropic anomalous Hall effect

Hung-Yu Yang, Bahadur Singh, Jonathan Gaudet +18

A developing frontier in condensed matter physics is the emergence of novel electromagnetic responses, such as topological and anomalous Hall effect (AHE), in ferromagnetic Weyl se…

cond-mat.mes-hall2015

Experimental discovery of a topological Weyl semimetal state in TaP

Su-Yang Xu, Ilya Belopolski, Daniel S. Sanchez +24

Weyl semimetals are expected to open up new horizons in physics and materials science because they provide the first realization of Weyl fermions and exhibit protected Fermi arc su…

cond-mat.mes-hall2015

Observation of the Adler-Bell-Jackiw chiral anomaly in a Weyl semimetal

Chenglong Zhang, Su-Yang Xu, Ilya Belopolski +16

We report the experimental discovery of Adler-Bell-Jackiw chiral anomaly in a Weyl semimetal crystal.

cond-mat.mtrl-sci2023

Observation of 2D Weyl Fermion States in Epitaxial Bismuthene

Qiangsheng Lu, P. V. Sreenivasa Reddy, Hoyeon Jeon +20

A two-dimensional (2D) Weyl semimetal featuring a spin-polarized linear band dispersion and a nodal Fermi surface is a new topological phase of matter. It is a solid-state realizat…

cond-mat.mes-hall2016

Observation of the spin-polarized surface state in a noncentrosymmetric superconductor BiPd

Madhab Neupane, Nasser Alidoust, M. Mofazzel Hosen +17

Recently, noncentrosymmetric superconductor BiPd has attracted considerable research interest due to the possibility of hosting topological superconductivity. Here we report a syst…

cond-mat.supr-con2026

Attention is all you need to solve chiral superconductivity

Chun-Tse Li, Tzen Ong, Max Geier +2

Recent advances on neural quantum states have shown that correlations between quantum particles can be efficiently captured by attention -- a foundation of modern neural architectu…