Article
Multidisciplinary Sciences
Rui Wang, Tigran A. Sedrakyan, Baigeng Wang, Lingjie Du, Rui-Rui Du
Summary: Correlation and frustration are important in physics, leading to new quantum phases. In this study, we observe the moat-band phenomena in shallowly inverted InAs/GaSb quantum wells, where we find an unconventional time-reversal-symmetry breaking excitonic ground state. We demonstrate the evolution from helical-like to chiral-like edge transport and explain our experimental observations using a moat band for excitons that results from density imbalance.
Article
Chemistry, Physical
Aiyun Luo, Zhida Song, Gang Xu
Summary: By using first-principles calculations and magnetic topological quantum chemistry, this study reveals the presence of fragile topological electronic states in the antiferromagnetic monolayer FeSe, which is very close to an antiferromagnetic topological insulator with robust edge states. These fragile topological states are captured by a double-degenerate nearly flat band just below the Fermi level. The S-4z symmetry is found to protect this fragile topology, leading to a 2D second-order topological insulator that supports a bound state with fractional charge e/2 at the corner of the sample. This work provides an important platform for studying the intriguing properties of magnetic fragile topological electronic states and can explain previous observations in the checkerboard antiferromagnetic monolayer FeSe.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Moon Jip Park, Sunam Jeon, SungBin Lee, Hee Chul Park, Youngkuk Kim
Summary: Higher-order topological insulator with topological corner states can be identified in twisted bilayer graphene systems through quantum oscillations. The tunneling of electrons between topological corner states leads to gate-tunable oscillations in the energy spectra, with oscillatory nodes indicating perfect suppression of tunneling and highlighting the topological nature of the corner states. A transport experiment is proposed for experimental realization of the oscillations, providing a feasible route to identify higher-order topological materials in twisted bilayer graphenes.
Article
Materials Science, Multidisciplinary
Yingyi Huang
Summary: We study the emergence of topological Floquet flat bands in alternating-twist multilayer graphene near the first magic angle. By applying a circularly polarized laser beam, a gap can be opened at the Moire K point, creating Floquet flat bands with non-zero Chern numbers. These dynamically produced topological flat bands can potentially be observed in experiments and offer a feasible way to realize the fractional Chern insulator.
Article
Chemistry, Multidisciplinary
Hao-Ke Xu, Mingqiang Gu, Fucong Fei, Yi-Sheng Gu, Dang Liu, Qiao-Yan Yu, Sha-Sha Xue, Xu-Hui Ning, Bo Chen, Hangkai Xie, Zhen Zhu, Dandan Guan, Shiyong Wang, Yaoyi Li, Canhua Liu, Qihang Liu, Fengqi Song, Hao Zheng, Jinfeng Jia
Summary: Research has discovered that MnBi4Te7 is a topological insulator with quantum anomalous Hall effect and axion insulator phase. Through scanning tunneling spectroscopy, it has been observed that there is an electronic state at the edge of the magnetic MnBi2Te4 layer at 4.5 K, but not in the nonmagnetic Bi2Te3 layer. As the temperature increases, the edge state disappears, while the state induced by point defects persists.
Article
Chemistry, Multidisciplinary
Kajetan M. Fijalkowski, Nan Liu, Pankaj Mandal, Steffen Schreyeck, Karl Brunner, Charles Gould, Laurens W. Molenkamp
Summary: The recent emergence of topological states of matter has led to significant discoveries, including the quantum anomalous Hall effect, which has potential applications in quantum metrology and impacts fundamental research in topological and magnetic states, as well as axion electrodynamics. This study presents electronic transport studies on a (V,Bi,Sb)2Te3 ferromagnetic topological insulator nanostructure in the quantum anomalous Hall regime, allowing examination of individual ferromagnetic domains. The observed telegraph noise in the Hall signal is attributed to magnetization fluctuations of the domain, and analysis of temperature and external magnetic field effects provides evidence for quantum tunneling of magnetization in a macrospin state.
Article
Materials Science, Multidisciplinary
Kazuaki Takasan, Shuntaro Sumita, Youichi Yanase
Summary: We demonstrate that finite current can induce topological phase transitions in superconductors by deforming the quasiparticle spectrum through the finite center-of-mass momentum of Cooper pairs. We examine the topological properties of three prototypical systems and show that all models exhibit current-induced topological phase transitions. We discuss the possibility of observing these phase transitions in experiments and their relation to other pairing states with finite center-of-mass momentum.
Article
Materials Science, Multidisciplinary
Guan-Hao Feng, Hong-Hao Zhang, Zhongbo Yan
Summary: This study demonstrates that various topological insulating phases can be found in bilayer Dirac materials, and intrinsic odd-parity superconductivity can arise in these systems through doping and short-range attractive interactions. The number and positions of Fermi surfaces result in different topological superconducting phases.
Article
Multidisciplinary Sciences
Martin Claassen, Lede Xian, Dante M. Kennes, Angel Rubio
Summary: The study predicts that twisted bilayers of ZrS2 with the group-IV metal Zr can form an emergent moire Kagome lattice with strong spin-orbit coupling, leading to novel topological quantum phases dominated by strong spin-orbit interactions. At small twist angles, ZrS2 heterostructures give rise to an emergent and twist-controlled moire Kagome lattice, combining geometric frustration and strong spin-orbit coupling to realize a moire quantum spin Hall insulator with highly controllable and nearly-dispersionless bands.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Hamed Vakil, Samiran Ganguly, George J. de Coster, Mahesh R. Neupane, Avik W. Ghosh
Summary: The surface state of a 3D topological insulator can be used for spin-orbit torque based switching, while the magnetization of a ferromagnet can control the surface current. By exploiting this reciprocal behavior, a 1-transistor 1-magnetic tunnel junction random access memory unit can be designed for ultra low power Processing-in-Memory architecture.
Article
Chemistry, Multidisciplinary
Shu Hsuan Su, Pei-Yu Chuang, Hsin-Yu Chen, Shih-Chang Weng, Wei-Chuan Chen, Ku-Ding Tsuei, Chao-Kuei Lee, Shih-Hsun Yu, Mitch M-C Chou, Li-Wei Tu, Horng-Tay Jeng, Chien-Ming Tu, Chih-Wei Luo, Cheng-Maw Cheng, Tay-Rong Chang, Jung-Chun Andrew Huang
Summary: The study demonstrates the topological proximity effect between antimonene and Sb2Te3, indicating the 2D material antimonene possesses a 2D topological state and forms Dirac fermions at the interface of a 2D normal insulator and a 3D topological insulator. By hydrogen etching Sb2Te3, the position of the Dirac point and shape of the Dirac surface state can be tuned, providing a new approach to create QSH systems in 2D-material TI heterostructures.
Article
Physics, Multidisciplinary
Shaowen Chen, Minhao He, Ya-Hui Zhang, Valerie Hsieh, Zaiyao Fei, K. Watanabe, T. Taniguchi, David H. Cobden, Xiaodong Xu, Cory R. Dean, Matthew Yankowitz
Summary: Twisted monolayer-bilayer graphene (tMBG) systems exhibit various correlated metallic and insulating states, as well as topological magnetic states. The phase diagram of tMBG can be switched under different perpendicular electric fields, providing a tunable platform for investigating correlated and topological states.
Article
Physics, Multidisciplinary
Daisuke Oshima, Satoshi Ikegaya, Andreas P. Schnyder, Yukio Tanaka
Summary: This paper studies the flat-band Majorana bound states in px-wave superconductors and proposes a promising device for effectively realizing px-wave superconductors. The emergence of flat-band Majorana bound states is demonstrated by calculating the local density of states.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Mengting Zhao, Yanyan Zhao, Yilian Xi, Hang Xu, Haifeng Feng, Xun Xu, Weichang Hao, Si Zhou, Jijun Zhao, Shi Xue Dou, Yi Du
Summary: This study demonstrates the electric-field controlled negative differential conductance in 2D vdW ferromagnet FGT, showing an atomic position dependence and precise modulation by altering the tunneling junction. The band shift and electric-field-driven 3d-orbital occupancy modulate the magnetic anisotropic energy in 2D FGT, leading to electric-field-tunable NDC, as confirmed by theoretical simulation. This work opens up possibilities for designing applications based on 2D vdW magnets.
Article
Materials Science, Multidisciplinary
Ka Ho Wong, Eric Mascot, Vidya Madhavan, Dale J. Van Harlingen, Dirk K. Morr
Summary: We present a theory that explains the behavior of differential shot noise and differential conductance in Majorana zero modes (MZMs) in a topological superconductor. Our results show that under certain conditions, the differential shot noise disappears while the differential conductance reaches a quantized value. This is found to be a universal characteristic of Majorana modes in two-dimensional topological superconductors.
Article
Physics, Condensed Matter
Maryam Khezerlou, Hadi Goudarzi, Samin Asgarifar
EUROPEAN PHYSICAL JOURNAL B
(2017)
Article
Physics, Applied
M. Roshanzamir-Nikou, H. Goudarzi
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2017)
Article
Engineering, Electrical & Electronic
Sayed Norollah Hedayat, Mohammad Taghi Ahmadi, Hassan Sedghi, Hadi Goudarzi, Shahram Moradi
JOURNAL OF NANOELECTRONICS AND OPTOELECTRONICS
(2017)
Article
Nanoscience & Nanotechnology
H. Goudarzi, M. Khezerlou, S. Asgarifar
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2017)
Article
Nanoscience & Nanotechnology
H. Goudarzi, M. Khezerlou, S. F. Ebadzadeh
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2018)
Article
Physics, Multidisciplinary
M. Khezerlou, H. Goudarzi, S. Asgarifar
Article
Physics, Condensed Matter
S. F. Ebadzadeh, H. Goudarzi, M. Khezerlou
PHYSICA B-CONDENSED MATTER
(2019)
Article
Physics, Condensed Matter
M. Khezerlou, H. Goudarzi
JOURNAL OF PHYSICS-CONDENSED MATTER
(2019)
Article
Physics, Multidisciplinary
M. Shahin, H. Goudarzi, M. Lotfizadeh
Article
Physics, Condensed Matter
S. Pashalou, H. Goudarzi, M. Khezerlou
JOURNAL OF PHYSICS-CONDENSED MATTER
(2020)
Article
Chemistry, Multidisciplinary
Mahdi Khaje, Hassan Sedghi, Hadi Goudarzi, Mohammad Taghi Ahmadi, Seyed Saeid Rahimian Koloor, Michal Petru
Article
Physics, Applied
Sina Pashalou, Hadi Goudarzi
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2020)
Article
Physics, Condensed Matter
Sina Pashalou, Hadi Goudarzi
SUPERLATTICES AND MICROSTRUCTURES
(2020)
Article
Materials Science, Multidisciplinary
S. Pashalou, H. Goudarzi, M. Khezerlou, S. A. Jafari
Summary: The study reveals that the interaction between optical pulse and Higgs mode oscillations in superconductors affects electron dynamics, leading to irreversible transitions between valence and conduction bands in graphene. The presence of superconductivity significantly influences the redistribution of conduction band electrons and hot spots in the Dirac points of graphene, with the number of hot spots depending on pulse intensity.
Article
Physics, Multidisciplinary
H. Goudarzi, S. S. Rashidi
INDIAN JOURNAL OF PHYSICS
(2017)