Publications (145)
Asynchronous Risk-Aware Multi-Agent Packet Routing for Ultra-Dense LEO Satellite Networks
Ke He, Thang X. Vu, Le He +3
The rise of ultra-dense LEO constellations creates a complex and asynchronous network environment, driven by their massive scale, dynamic topologies, and significant delays. This u…
Evidence for electron-electron interaction in topological insulator thin films
Jian Wang, Ashley M. DaSilva, Cui-Zu Chang +6
We consider in our work high quality single crystal thin films of Bi2Se3, grown by molecular beam epitaxy, both with and without Pb doping. Our ARPES data demonstrate topological s…
Reentrant quantum anomalous Hall effect in molecular beam epitaxy-grown MnBi2Te4 thin films
Yuanzhao Li, Yunhe Bai, Yang Feng +16
In this study, we investigate intrinsic magnetic topological insulator MnBi2Te4 thin films grown by molecular beam epitaxy. We observe a reentrant quantum anomalous Hall effect whe…
Enhanced electron dephasing in three-dimensional topological insulators
Jian Liao, Yunbo Ou, Haiwen Liu +4
Study of the dephasing in electronic systems is not only important for probing the nature of their ground states, but also crucial to harnessing the quantum coherence for informati…
Fermi Level Tuning of Epitaxial Sb2Te3 Thin Films on Graphene by Regulating Intrinsic Defects and Substrate Transfer Doping
Yeping Jiang, Y. Y. Sun, Mu Chen +9
High-quality Sb2Te3 films are obtained by molecular beam epitaxy on graphene substrate and investigated by in situ scanning tunneling microscopy/spectroscopy. Intrinsic defects res…
Ambi-chiral anomalous Hall effect in magnetically doped topological insulators
Chang Liu, Yunyi Zang, Yan Gong +4
The chirality associated with broken time reversal symmetry in magnetically doped topological insulators has important implications to the quantum transport phenomena. Here we repo…
Band structure engineering in (Bi1-xSbx)2Te3 ternary topological insulators
Jinsong Zhang, Cui-Zu Chang, Zuocheng Zhang +10
Three-dimensional (3D) topological insulators (TI) are novel quantum materials with insulating bulk and topologically protected metallic surfaces with Dirac-like band structure. Th…
Mass acquisition of Dirac fermions in Cr-doped topological insulator Sb2Te3 films
Yeping Jiang, Zhi Li, Canli Song +7
We introduce time-reversal-symmetry breaking by doping Cr atoms into the topmost quintuple layer or into the bulk of Sb2Te3 thin films. We find that even at a high Cr-doping level…
Experimental Proof of Universal Conductance Fluctuation in Quasi-1D Epitaxial BiSe Wires
Sadashige Matsuo, Kensaku Chida, Daichi Chiba +8
We report on conductance fluctuation in quasi-one-dimensional wires made of epitaxial BiSe thin film. We found that this type of fluctuation decreases as the wire lengt…
Growth dynamics and thickness-dependent electronic structure of topological insulator Bi2Te3 thin films on Si
Yao-Yi Li, Guang Wang, Xie-Gang Zhu +16
We use real-time reflection high energy electron diffraction intensity oscillation to establish the Te-rich growth dynamics of topological insulator thin films of Bi2Te3 on Si(111)…
Observation of tunneling gap in epitaxial ultrathin films of pyrite-type copper disulfide
Chong Liu, Haohao Yang, Can-Li Song +5
We report scanning tunneling microscopy investigation on epitaxial ultrathin films of pyrite-type copper disulfide. Layer by layer growth of CuS2 films with a preferential orientat…
QoS-Aware Hierarchical Reinforcement Learning for Joint Link Selection and Trajectory Optimization in SAGIN-Supported UAV Mobility Management
Jiayang Wan, Ke He, Yafei Wang +3
Due to the significant variations in unmanned aerial vehicle (UAV) altitude and horizontal mobility, it becomes difficult for any single network to ensure continuous and reliable t…
Experimental observation of Dirac-like surface states and topological phase transition in PbSnTe(111) films
Chenhui Yan, Junwei Liu, Yunyi Zang +12
The surface of a topological crystalline insulator (TCI) carries an even number of Dirac cones protected by crystalline symmetry. We epitaxially grew high quality PbSnT…
Incommensurate smectic phase in close proximity to the high-Tc superconductor FeSe/SrTiO3
Yonghao Yuan, Xuemin Fan, Xintong Wang +4
Superconductivity is significantly enhanced in monolayer FeSe grown on SrTiO3, but not for multilayer films, in which large strength of nematicity develops. However, the link betwe…
Experimental demonstration of the topological surface states protected by the time-reversal symmetry
Tong Zhang, Peng Cheng, Xi Chen +9
We report direct imaging of standing waves of the nontrivial surface states of topological insulator BiTe by using a low temperature scanning tunneling microscope. The inte…
Direct observation of high temperature superconductivity in one-unit-cell FeSe films
Wenhao Zhang, Yi Sun, Jinsong Zhang +26
Heterostructure based interface engineering has been proved an effective method for finding new superconducting systems and raising superconductivity transition temperature (TC). I…
Presence versus absence of charging energies in PbTe quantum dots
Yuhao Wang, Lining Yang, Wenyu Song +18
Charging energy () is essential in quantum dot (QD) devices. Previous studies on PbTe QDs have reported both the presence and absence of . To resolve this ambiguity, we v…
Atomic Visualization of Copper Oxide Structure in Infinite-Layer Cuprate SrCuO2
Yong Zhong, Sha Han, Yang Wang +8
We report on atomic-scale visualization of the structure of infinite-layer cuprate SrCuO2 thin films grown on Nb-doped SrTiO3 substrates by molecular beam epitaxy. In-situ scanning…
Magnetic properties of molecular beam epitaxy-grown ultrathin Cr2Ge2Te6 films down to monolayer limit on Si substrates
Pengfei Ji, Ruixuan Liu, Tianchen Zhu +13
Cr2Ge2Te6, a prototypical van der Waals ferromagnetic semiconductor, have attracted significant interest for its potential applications in high-performance spintronics. However, th…
Quantized anomalous Hall resistivity achieved in molecular beam epitaxy-grown MnBi2Te4 thin films
Yunhe Bai, Yuanzhao Li, Jianli Luan +17
The intrinsic magnetic topological insulator MnBi2Te4 provides a feasible pathway to high temperature quantum anomalous Hall (QAH) effect as well as various novel topological quant…
Crossover between Weak Antilocalization and Weak Localization of Bulk States in Ultrathin Bi2Se3 Films
Huichao Wang, Haiwen Liu, Cui-Zu Chang +9
We report transport studies on the 5 nm thick Bi2Se3 topological insulator films which are grown via molecular beam epitaxy technique. The angle-resolved photoemission spectroscopy…
Superconductivity dichotomy in K-coated single and double unit cell FeSe films on SrTiO3
Chenjia Tang, Ding Zhang, Yunyi Zang +12
We report the superconductivity evolution of one unit cell (1-UC) and 2-UC FeSe films on SrTiO3(001) substrates with potassium (K) adsorption. By in situ scanning tunneling spectro…
Dimensional crossover and topological nature of the thin films of a three-dimensional topological insulator by band gap engineering
Zhenyu Wang, Tong Zhou, Tian Jiang +10
Identification and control of topological phases in topological thin films offer great opportunity for fundamental research and the fabrication of topology-based devices. Here, com…
Field-effect Modulation of Anomalous Hall Effect in Diluted Ferromagnetic Topological Insulator Epitaxial Films
Cui-Zu Chang, Min-Hao Liu, Zuo-Cheng Zhang +3
High quality chromium (Cr) doped three-dimensional topological insulator (TI) Sb2Te3 films are grown via molecular beam epitaxy on heat-treated insulating SrTiO3(111) substrates. W…
SCA-LLM: Spectral-Attentive LLM-Based Wireless World Modeling for Agentic Communications
Ke He, Le He, Lisheng Fan +4
Future AI-native wireless networks are moving from reactive optimization to agentic decision-making that can sense, predict, and plan under fast-varying channels. This calls for wi…
Liuer Mihou: A Practical Framework for Generating and Evaluating Grey-box Adversarial Attacks against NIDS
Ke He, Dan Dongseong Kim, Jing Sun +3
Due to its high expressiveness and speed, Deep Learning (DL) has become an increasingly popular choice as the detection algorithm for Network-based Intrusion Detection Systems (NID…
Interference Evidence for Rashba-Type Spin-Split on Semimetallic WTe2 Surface
Qing Li, Jiaqiang Yan, Biao Yang +11
Semimetallic tungsten ditelluride (WTe2) displays an extremely large non-saturating magnetoresistance (XMR), which is the subject of intense interest. This phenomenon is thought to…
Correlation between magnetic domain structures and quantum anomalous Hall effect in epitaxial MnBi2Te4 thin films
Yang Shi, Yunhe Bai, Yuanzhao Li +16
We use magnetic force microscopy (MFM) to study spatial uniformity of magnetization of epitaxially grown MnBi2Te4 thin films. Compared to films which exhibit no quantum anomalous H…
Proximity effect in PbTe-Pb hybrid nanowire Josephson junctions
Zitong Zhang, Wenyu Song, Yichun Gao +20
Semiconductor-superconductor hybrid nanowires are a leading material platform for the realization of Majorana zero modes. The semiconductors in previous studies are dominantly InAs…
Realization of Stable Ferromagnetic Order in Topological Insulator: Codoping Enhanced Magnetism in 4f Transition Metal Doped Bi2Se3
Bei Deng, Yiou Zhang, S. B. Zhang +3
The realization of long range and insulating ferromagnetic states in topological insulator (TI) has been a pressing issue since its discovery. Only recently, such state was achieve…
Universally optimizable strategy for magnetic gaps towards high-temperature quantum anomalous Hall states via magnetic-insulator/topological-insulator building-blocks
Zhe Li, Feng Xue, Xin-Yi Tang +4
Optimizing the magnetic Zeeman-splitting term, specifically the magnetic gap of the topological surface states (TSSs), is a crucial issue and central challenge in advancing higher-…
Conductance Quantization in PbTe Nanowires
Wenyu Song, Yuhao Wang, Wentao Miao +17
PbTe nanowires coupled to a superconductor have recently been proposed as a potential Majorana platform. The hallmark of the one-dimensional nature of ballistic nanowires is their…
Interplay between electronic dephasing and localization in finite-sized Chern insulator
Yunhe Bai, Yuanzhao Li, Jianli Luan +14
Anderson localization is anticipated to play a pivotal role in the manifestation of the quantum anomalous Hall effect, akin to its role in conventional quantum Hall effects. The si…
Detection of a superconducting phase in a two-atom layer of hexagonal Ga film grown on semiconducting GaN(0001)
Huimin Zhang, Yi Sun, Wei Li +21
The recent observation of superconducting state at atomic scale has motivated the pursuit of exotic condensed phases in two-dimensional (2D) systems. Here we report on a supercondu…
Imaging the Electron-Boson Coupling in Superconducting FeSe
Can-Li Song, Yi-Lin Wang, Ye-Ping Jiang +7
Scanning tunneling spectroscopy has been used to reveal signatures of a bosonic mode in the local quasiparticle density of states of superconducting FeSe films. The mode appears be…
WARDEN: Multi-Directional Backdoor Watermarks for Embedding-as-a-Service Copyright Protection
Anudeex Shetty, Yue Teng, Ke He +1
Embedding as a Service (EaaS) has become a widely adopted solution, which offers feature extraction capabilities for addressing various downstream tasks in Natural Language Process…
Interface induced high temperature superconductivity in single unit-cell FeSe films on SrTiO3
Qing-Yan Wang, Zhi Li, Wen-Hao Zhang +17
Searching for superconducting materials with high transition temperature (TC) is one of the most exciting and challenging fields in physics and materials science. Although supercon…
Intrinsic and tunable quantum anomalous Hall effect and magnetic topological phases in XYBi2Te5
Xin-Yi Tang, Zhe Li, Feng Xue +6
By first-principles calculations, we study the magnetic and topological properties of XYBi2Te5-family (X, Y = Mn, Ni, V, Eu) compounds. The strongly coupled double magnetic atom-la…
Chemical potential dependent gap-opening at the Dirac surface states of Bi2Se3 induced by aggregated substitutional Cr atoms
Cui-Zu Chang, Peizhe Tang, Yi-Lin Wang +11
With angle-resolved photoemission spectroscopy, gap-opening is resolved at up to room temperature in the Dirac surface states of molecular beam epitaxy grown Cr-doped Bi2Se3 topolo…
Experimental realization of an intrinsic magnetic topological insulator
Yan Gong, Jingwen Guo, Jiaheng Li +21
Intrinsic magnetic topological insulator (TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can p…
Anisotropy of PbTe nanowires with and without a superconductor
Zonglin Li, Wenyu Song, Shan Zhang +17
We investigate the anisotropic behaviors in PbTe and PbTe-Pb hybrid nanowires. In previous studies on PbTe, wire-to-wire variations in anisotropy indicate poor device control, posi…
Molecular Beam Epitaxy Growth of Superconducting LiFeAs Film on SrTiO3(001) Substrate
Kai Chang, Peng Deng, Teng Zhang +8
The stoichiometric "111" iron-based superconductor, LiFeAs, has attacted great research interest in recent years. For the first time, we have successfully grown LiFeAs thin film by…
Dimensional Crossover Induced Topological Hall Effect in a Magnetic Topological Insulator
Chang Liu, Yunyi Zang, Wei Ruan +5
We report transport studies of Mn-doped Bi2Te3 topological insulator (TI) films with accurately controlled thickness grown by molecular beam epitaxy. We find that films thicker tha…
Numerical study of PbTe-Pb hybrid nanowires for engineering Majorana zero modes
Zhan Cao, Dong E. Liu, Wan-Xiu He +3
Epitaxial semiconductor-superconductor (SM-SC) hybrid nanowires are potential candidates for implementing Majorana qubits. Recent experimental and theoretical works show that charg…
Chern insulator phase realized in dual-gate-tuned MnBi2Te4 thin films grown by molecular beam epitaxy
Yunhe Bai, Yuanzhao Li, Ruixuan Liu +19
The intrinsic magnetic order, large topological-magnetic gap and rich topological phases make MnBi2Te4 a wonderful platform to study exotic topological quantum states such as axion…
Growth of quantum well films of topological insulator Bi2Se3 on insulating substrate
Cui-Zu Chang, Ke He, Min-Hao Liu +6
Insulating substrates are crucial for electrical transport study and room temperature application of topological insulator films at thickness of only several nanometers. High quali…
Edge states at nematic domain walls in FeSe films
Yonghao Yuan, Wei Li*, Bin Liu +9
Quantum spin Hall (QSH) effect is an intriguing phenomenon arising from the helical edge states in two-dimensional topological insulators. We use molecular beam epitaxy (MBE) to pr…
Observation of Anderson localization in ultrathin films of three-dimensional topological insulators
Jian Liao, Yunbo Ou, Xiao Feng +8
Anderson localization, the absence of diffusive transport in disordered systems, has been manifested as hopping transport in numerous electronic systems, whereas in recently discov…
Interface enhanced electron-phonon coupling and high temperature superconductivity in potassium-coated ultra-thin FeSe films on SrTiO3
Chenjia Tang, Chong Liu, Guanyu Zhou +10
Alkali-metal (potassium) adsorption on FeSe thin films with thickness from two unit cells (UC) to 4-UC on SrTiO3 grown by molecular beam epitaxy is investigated with a low-temperat…
Electrostatic effects of the MnBi2Te4-superconductor hetero-structures in chiral Majorana search
Li Chen, Zhan Cao, Ke He +2
The realization of chiral Majorana modes is a challenging task. We aim to comprehend the phase diagrams and parameter control capabilities of the actual devices used in the chiral…
Interface induced high temperature superconductivity in single unit-cell FeSe films on SrTiO3(110)
Guanyu Zhou, Ding Zhang, Chong Liu +9
We report high temperature superconductivity in one unit-cell (1-UC) FeSe films grown on STO(110) substrate by molecular beam epitaxy. By in-situ scanning tunneling spectroscopy me…
Weak Antilocalization and Conductance Fluctuation in a Sub-micrometer-sized Wire of Epitaxial Bi2Se3
Sadashige Matsuo, Tomohiro Koyama, Kazutoshi Shimamura +9
In this study, we address the phase coherent transport in a sub-micrometer-sized Hall bar made of epitaxial Bi2Se3 thin film by probing the weak antilocalization (WAL) and the magn…
Thickness-Induced Topological Phase Transition Investigated by Helicity Dependent Photocurrent in -Sn/CdTe(110)
Tengfei Liu, Xiyu Hong, Zhe Li +10
-Sn exhibits a rich topological phase diagram, yet experimental methods to tune and distinguish these phases remain limited. Here, we investigated the helicity-dependent photoc…
Superconductivity in Few-Layer Stanene
Menghan Liao, Yunyi Zang, Zhaoyong Guan +11
A single atomic slice of α-tin-stanene-has been predicted to host quantum spin Hall effect at room temperature, offering an ideal platform to study low-dimensional and topological…
Power-Law Decay of Standing Waves on the Surface of Topological Insulators
Jing Wang, Wei Li, Peng Cheng +9
We propose a general theory on the standing waves (quasiparticle interference pattern) caused by the scattering of surface states off step edges in topological insulators, in which…
Crossover of Three-Dimensional Topological Insulator of Bi2Se3 to the Two-Dimensional Limit
Yi Zhang, Ke He, Cui-Zu Chang +13
Bi2Se3 is theoretically predicted1 2and experimentally observed2,3 to be a three dimensional topological insulator. For possible applications, it is important to understand the ele…
Simultaneous electrical-field-effect modulation of both top and bottom Dirac surface states of epitaxial thin films of three-dimensional topological insulators
Cui-Zu Chang, Zuocheng Zhang, Kang Li +11
It is crucial for the studies of the transport properties and quantum effects related to Dirac surface states of three-dimensional topological insulators (3D TIs) to be able to sim…
Coulomb gap induced by electronic correlation and enlarged superconducting gap in laterally confined Pb islands grown on SrTiO3
Yonghao Yuan, Xintong Wang, Canli Song +6
We report high-resolution scanning tunneling microscopy (STM) study of nano-sized Pb islands grown on SrTiO3, where three distinct types of gaps with different energy scales are re…
Robust axion insulator and Chern insulator phases in a two-dimensional antiferromagnetic topological insulator
Chang Liu, Yongchao Wang, Hao Li +7
The intricate interplay between nontrivial topology and magnetism in two-dimensional (2D) materials has led to the emergence of many novel phenomena and functionalities. An outstan…
Current induced anisotropic magnetoresistance in topological insulator films
Jian Wang, Handong Li, Cui-Zu Chang +7
Topological insulators are insulating in the bulk but possess spin-momentum locked metallic surface states protected by time-reversal symmetry. The existence of these surface state…
Type-II Ising Pairing in Few-Layer Stanene
Joseph Falson, Yong Xu, Menghan Liao +11
Spin-orbit coupling has proven indispensable in realizing topological materials and more recently Ising pairing in two-dimensional superconductors. This pairing mechanism relies on…
LongCat-Flash Technical Report
Meituan LongCat Team, Bayan, Bei Li +179
We introduce LongCat-Flash, a 560-billion-parameter Mixture-of-Experts (MoE) language model designed for both computational efficiency and advanced agentic capabilities. Stemming f…
Crossover between weak localization and weak antilocalization in magnetically doped topological insulator
Minhao Liu Jinsong Zhang, Cui-Zu Chang, Zuocheng Zhang +10
Topological insulators (TI) are a new class of quantum materials with insulating bulk enclosed by topologically protected metallic boundaries. The surface states of three-dimension…
Plateau regions for zero-bias peaks within 5% of the quantized conductance value
Zhaoyu Wang, Huading Song, Dong Pan +13
Probing an isolated Majorana zero mode is predicted to reveal a tunneling conductance quantized at at zero temperature. Experimentally, a zero-bias peak (ZBP) is expected…
FeCaffe: FPGA-enabled Caffe with OpenCL for Deep Learning Training and Inference on Intel Stratix 10
Ke He, Bo Liu, Yu Zhang +2
Deep learning and Convolutional Neural Network (CNN) have becoming increasingly more popular and important in both academic and industrial areas in recent years cause they are able…
Demonstration of surface transport in a hybrid Bi2Se3/Bi2Te3 heterostructure
Yanfei Zhao, Cui-Zu Chang, Ying Jiang +9
In spite of much work on topological insulators (TIs), systematic experiments for TI/TI heterostructures remain absent. We grow a high quality heterostructure containing single qui…
Direct observation of quantum confinement of massless Dirac fermions in a topological insulator
Mu Chen, Zhen-Guo Fu, Jun-Ping Peng +9
Since the discovery of topological insulators (TIs)1,2, the peculiar nature of their chiral surface states has been experimentally demonstrated both in bulk and in film materials w…
Gate-tunable subband degeneracy in semiconductor nanowires
Yuhao Wang, Wenyu Song, Zhan Cao +20
Degeneracy and symmetry have a profound relation in quantum systems. Here, we report gate-tunable subband degeneracy in PbTe nanowires with a nearly symmetric cross-sectional shape…
Quantum and Classical Magnetoresistance in Ambipolar Topological Insulator Transistors with Gate-tunable Bulk and Surface Conduction
Jifa Tian, Cuizu Chang, Helin Cao +4
Weak antilocalization (WAL) and linear magnetoresistance (LMR) are two most commonly observed magnetoresistance (MR) phenomena in topological insulators (TIs) and often attributed…
Topology hierarchy of transition metal dichalcogenides built from quantum spin Hall layers
Lixuan Xu, Yiwei Li, Yuqiang Fang +15
The evolution of the physical properties of two-dimensional material from monolayer limit to the bulk reveals unique consequences from dimension confinement and provides a distinct…
Electronic states and magnetic response of MnBi2Te4 by scanning tunneling microscopy and spectroscopy
Yonghao Yuan, Xintong Wang, Hao Li +10
Exotic quantum phenomena have been demonstrated in recently discovered intrinsic magnetic topological insulator MnBi2Te4. At its two-dimensional limit, quantum anomalous Hall (QAH)…
Gate-Variable Mid-Infrared Optical Transitions in a Topological Insulator
William S. Whitney, Victor W. Brar, Yunbo Ou +6
We report mid-infrared spectroscopy measurements of an electrostatically gated topological insulator, in which we observe several percent modulation of transmittance and reflectanc…
Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
Cui-Zu Chang, Jinsong Zhang, Xiao Feng +20
The quantized version of the anomalous Hall effect has been predicted to occur in magnetic topological insulators, but the experimental realization has been challenging. Here, we r…
Selective area epitaxy of PbTe-Pb hybrid nanowires on a lattice-matched substrate
Yuying Jiang, Shuai Yang, Lin Li +17
Topological quantum computing is based on braiding of Majorana zero modes encoding topological qubits. A promising candidate platform for Majorana zero modes is semiconductor-super…
Observation of the zero Hall plateau in a quantum anomalous Hall insulator
Yang Feng, Xiao Feng, Yunbo Ou +10
Quantum anomalous Hall (QAH) effect in magnetic topological insulator (TI) is a novel transport phenomenon in which the Hall resistance reaches the quantum plateau in the absence o…
Magnetic quantum phase transition in Cr-doped Bi2(SexTe1-x)3 driven by the Stark effect
Zuocheng Zhang, Xiao Feng, Jing Wang +11
The interplay between magnetism and topology, as exemplified in the magnetic skyrmion systems, has emerged as a rich playground for finding novel quantum phenomena and applications…
Gate Tunable Supercurrent in Josephson Junctions Based on Bi2Te3 Topological Insulator Thin Films
Wei-Xiong Wu, Yang Feng, Yun-He Bai +13
We report transport measurements on Josephson junctions consisting of Bi2Te3 topological insulator (TI) thin films contacted by superconducting Nb electrodes. For a device with jun…
Anomalous Fraunhofer-like patterns in quantum anomalous Hall Josephson junction
Junjie Qi, Haiwen Liu, Jie Liu +5
The intriguing interplay between topology and superconductivity has attracted significant attention, given its potential for realizing topological superconductivity. In the quantum…
Excess photon-assisted noise of Majorana and Andreev bound states
Qiang Lin, Ying-Xin Liang, Ke He +1
Photon-assisted tunneling arises under an ac bias, with the drive frequency setting the photon energy. The excess photon-assisted noise is defined as the difference between the sho…
Quantized Andreev conductance in semiconductor nanowires
Yichun Gao, Wenyu Song, Yuhao Wang +20
Clean one-dimensional electron systems can exhibit quantized conductance. The plateau conductance doubles if the transport is dominated by Andreev reflection. Here, we report quant…
Hard superconducting gap in PbTe nanowires
Yichun Gao, Wenyu Song, Shuai Yang +15
Semiconductor nanowires coupled to a superconductor provide a powerful testbed for quantum device physics such as Majorana zero modes and gate-tunable hybrid qubits. The performanc…
Multimechanism quantum anomalous Hall and Chern number tunable states in germanene (silicene, stanene)/BiTe heterostructures
Zhe Li, Jiatong Zhang, Xiyu Hong +2
By constructing germanene (silicene, stanene)/BiTe ( = 3d-transition elements) heterostructures, we discovered and designed multimechanism quantum-anomalous-Hall (QAH…
Superconductivity in a single layer alkali-doped FeSe: a weakly coupled two-leg ladder system
Wei Li, Hao Ding, Pengfei Zhang +10
We prepare single layer potassium-doped iron selenide (110) film by molecular beam expitaxy. Such a single layer film can be viewed as a two-dimensional system composed of weakly c…
Experimental Observation of Topological Superconductivity and Majorana Zero Modes on beta-Bi2Pd Thin Films
Yan-Feng Lv, Wen-Lin Wang, Yi-Min Zhang +7
Using a cryogenic scanning tunneling microscopy, we report the observation of topologically nontrivial superconductivity on a single material of β-Bi2Pd films grown by molecular b…
Topological insulator Bi2Se3 thin films grown on double-layer graphene by molecular beam epitaxy
Can-Li Song, Yi-Lin Wang, Ye-Ping Jiang +14
Atomically flat thin films of topological insulator Bi2Se3 have been grown on double-layer graphene formed on 6H-SiC(0001) substrate by molecular beam epitaxy. By a combined study…
Phase Separation and Magnetic Order in K-doped Iron Selenide Superconductor
Wei Li, Hao Ding, Peng Deng +8
Alkali-doped iron selenide is the latest member of high Tc superconductor family, and its peculiar characters have immediately attracted extensive attention. We prepared high-quali…
Global PIQA: Evaluating Commonsense Reasoning Across 100+ Languages and Cultures
Tyler A. Chang, Catherine Arnett, Abdelrahman Sadallah +377
To date, there exist almost no culturally-specific evaluation benchmarks for large language models (LLMs) that cover a large number of languages and cultures. In this paper, we pre…
Landau Quantization of Massless Dirac Fermions in Topological Insulator
Peng Cheng, Canli Song, Tong Zhang +17
The recent theoretical prediction and experimental realization of topological insulators (TI) has generated intense interest in this new state of quantum matter. The surface states…
Towards Optimally Efficient Search with Deep Learning for Large-Scale MIMO Systems
Le He, Ke He, Lisheng Fan +3
This paper investigates the optimal signal detection problem with a particular interest in large-scale multiple-input multiple-output (MIMO) systems. The problem is NP-hard and can…
Intrinsic magnetic topological insulators in van der Waals layered MnBiTe-family materials
Jiaheng Li, Yang Li, Shiqiao Du +6
The interplay of magnetism and topology is a key research subject in condensed matter physics and material science, which offers great opportunities to explore emerging new physics…
Nodeless pairing in superconducting copper-oxide monolayer films on Bi2Sr2CaCu2O8+δ
Yong Zhong, Yang Wang, Sha Han +13
The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most ef…
Band engineering of Dirac surface states in topological insulators-based van der Waals heterostructures
Cui-Zu Chang, Peizhe Tang, Xiao Feng +5
The existence of gapless Dirac surface band of a three dimensional (3D) topological insulator (TI) is guaranteed by the non-trivial topological character of the bulk band, yet the…
Strong enhancement of g-factor in PbTe-Pb hybrid nanowires
Shan Zhang, Wenyu Song, Zonglin Li +17
We report large Lande g-factors observed in PbTe-Pb hybrid nanowires. The g-factor can reach 83, significantly larger than those in bare PbTe nanowires (typically below 20). We att…
Direct evidence of ferromagnetism in a quantum anomalous Hall system
Wenbo Wang, Yunbo Ou, Chang Liu +4
Quantum anomalous Hall (QAH) systems are of great fundamental interest and potential application because of their dissipationless conduction without the need for external magnetic…
Molecular beam epitaxy growth and scanning tunneling microscopy study of TiSe ultrathin films
Jun-Ping Peng, Jia-Qi Guan, Hui-Min Zhang +5
Molecular beam epitaxy is used to grow TiSe2 ultrathin films on graphitized SiC(0001) substrate. TiSe2films proceed via a nearly layer-by-layer growth mode and exhibit two dominant…
Electron interaction-driven insulating ground state in Bi2Se3 topological insulators in the two dimensional limit
Minhao Liu, Cui-Zu Chang, Zuocheng Zhang +10
We report a transport study of ultrathin Bi2Se3 topological insulators with thickness from one quintuple layer to six quintuple layers grown by molecular beam epitaxy. At low tempe…
Atomically Resolved FeSe/SrTiO3(001) Interface Structure by Scanning Transmission Electron Microscopy
Fangsen Li, Qinghua Zhang, Chenjia Tang +14
Interface-enhanced high-temperature superconductivity in one unit-cell (UC) FeSe films on SrTiO3(001) (STO) substrate has recently attracted much attention in condensed matter phys…
Landau quantization and the thickness limit of topological insulator thin films of Sb2Te3
Yeping Jiang, Yilin Wang, Mu Chen +7
We report the experimental observation of Landau quantization of molecular beam epitaxy grown Sb2Te3 thin films by a low-temperature scanning tunneling microscope. Different from a…
Edge supercurrent in Josephson junctions based on topological materials
Junjie Qi, Chui-Zhen Chen, Juntao Song +4
The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum computing. The Josephson effect…
Electrically tuned magnetic order and magnetoresistance in a topological insulator
Zuocheng Zhang, Xiao Feng, Minghua Guo +10
The Dirac-like surface states of the topological insulators (TIs) are protected by time reversal symmetry (TRS) and exhibit a host of novel properties. Introducing magnetism into T…