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The realization of fractional Chern insulators in moir\'e materials has sparked the search for further novel phases of matter in this platform. In particular, recent works have demonstrated the possibility of realizing quantum anomalous…

Mesoscale and Nanoscale Physics · Physics 2025-07-29 Raul Perea-Causin , Hui Liu , Emil J. Bergholtz

The use of topological invariants to describe geometric phases of quantum matter has become an essential tool in modern solid state physics. The first instance of this paradigmatic trend can be traced to the study of the quantum Hall…

Mathematical Physics · Physics 2017-05-19 Domenico Monaco

The topological invariants of a time-reversal-invariant band structure in two dimensions are multiple copies of the $\mathbb{Z}_2$ invariant found by Kane and Mele. Such invariants protect the topological insulator and give rise to a spin…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 J. E. Moore , L. Balents

Topological matter is a trending topic in condensed matter: From a fundamental point of view it has introduced new phenomena and tools, and for technological applications, it holds the promise of basic stable quantum computing. Similarly,…

Disordered Systems and Neural Networks · Physics 2016-08-29 Eduardo V. Castro , Raphael de Gail , M. Pilar López-Sancho , María A. H. Vozmediano

In non-interacting systems, bands from non-trivial topology emerge strictly at half-filling and exhibit either the quantum anomalous Hall or spin Hall effects. Here we show using determinantal quantum Monte Carlo and an exactly solvable…

Mesoscale and Nanoscale Physics · Physics 2023-09-29 Peizhi Mai , Jinchao Zhao , Benjamin E. Feldman , Philip W. Phillips

The observation of new insulating phases of two-dimensional electrons in the first excited Landau level is reported. These states, which are manifested as re-entrant integer quantized Hall effects, exist alongside well-developed…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 J. P. Eisenstein , K. B. Cooper , L. N. Pfeiffer , K. W. West

We study a bilayer two-dimension-electron-gas (2DEG) adjacent to a type-II superconductor thin film with a pinned vortex lattice. We find that with increasing interlayer tunneling, the system of half filling presents three phases: gapped…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Ningning Hao , Wei Zhang , Zhigang Wang , Yupeng Wang , Ping Zhang

Motivated by recent transport experiments, we theoretically study the quantum Hall effect in topological semimetal films. Owing to the confinement effect, the bulk subbands originating from the chiral Landau levels establish energy gaps…

Mesoscale and Nanoscale Physics · Physics 2021-07-13 D. -H. -Minh Nguyen , Koji Kobayashi , Jan-Erik R. Wichmann , Kentaro Nomura

Quasi-periodically driven quantum systems are predicted to exhibit quantized topological properties, in analogy with the quantized transport properties of topological insulators. We use a single nitrogen-vacancy center in diamond to…

Mesoscale and Nanoscale Physics · Physics 2020-10-21 Eric Boyers , Philip J. D. Crowley , Anushya Chandran , Alexander O. Sushkov

The quantum Hall effect is one of the most important developments in condensed matter physics of the 20th century. The standard explanations of the famous integer quantized Hall plateaus in the transverse resistivity are qualitative, and…

Mesoscale and Nanoscale Physics · Physics 2008-11-24 Tobias Kramer , Eric J. Heller , Robert E. Parrott , Chi-Te Liang , C. F. Huang , Kuang Yao Chen , Li-Hung Lin , Jau-Yang Wu , Sheng-Di Lin

We study the quantum Hall effect in the surface states of topological insulator in the presence of a perpendicular magnetic field in the framework of edge states. Motion of Dirac fermions will form descrete Landau levels, among which a…

Mesoscale and Nanoscale Physics · Physics 2009-09-24 Shun-Qing Shen

Two-dimensional Dirac semimetals with a single massless Dirac cone exhibit the parity anomaly. Usually, such a kind of anomalous topological semimetallic phase in real materials is unstable where any amount of disorder can drive it into a…

Mesoscale and Nanoscale Physics · Physics 2023-09-14 Zhen Ning , Xianyong Ding , Dong-Hui Xu , Rui Wang

We report magneto-transport measurements in wide GaAs quantum wells with tunable density to probe the stability of the fractional quantum Hall effect at filling factor $\nu = $ 5/2 in the vicinity of the crossing between Landau levels (LLs)…

Mesoscale and Nanoscale Physics · Physics 2012-03-06 Yang Liu , D. Kamburov , M. Shayegan , L. N. Pfeiffer , K. W. West , K. W. Baldwin

The anomalous spin Hall conductivity in the holographic model of Dirac semimetals with two Dirac nodes protected by the crystal symmetry has been elaborated. Such system besides the chiral anomaly possesses another anomaly which is related…

High Energy Physics - Theory · Physics 2021-10-19 Bartłomiej Kiczek , Marek Rogatko , Karol I. Wysokiński

Exploration of the novel relationship between magnetic order and topological semimetals has received enormous interest in a wide range of both fundamental and applied research. Here we predict that soft ferromagnetic (FM) material EuB6 can…

Materials Science · Physics 2020-02-26 Simin Nie , Yan Sun , Fritz B. Prinz , Zhijun Wang , Hongming Weng , Zhong Fang , Xi Dai

We report an unconventional quantum spin Hall phase in the monolayer T$_\text{d}$-WTe$_2$, which exhibits hitherto unknown features in other topological materials. The low-symmetry of the structure induces a canted spin texture in the $yz$…

Mesoscale and Nanoscale Physics · Physics 2021-01-04 Jose H. Garcia , Marc Vila , Chuang-Han Hsu , Xavier Waintal , Vitor M. Pereira , Stephan Roche

Stacked two dimensional electron systems in transverse magnetic fields exhibit three dimensional fractional quantum Hall phases. We analyze the simplest such phases and find novel bulk properties, e.g., irrational braiding. These phases…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. D. Naud , Leonid P. Pryadko , S. L. Sondhi

Topological quantum numbers are often used to characterise the topological order of phase having protected gapless edge modes when the system is kept in a space with the boundary. The famous examples in this category are the quantized…

Mesoscale and Nanoscale Physics · Physics 2024-07-09 Saurabh Kumar Srivastav , Anindya Das

The recent measurement of a half-integer thermal conductance for the $\nu=5/2$ fractional quantum Hall state has confirmed its non-Abelian nature, making the question of the underlying topological order highly intriguing. We analyze the…

Mesoscale and Nanoscale Physics · Physics 2020-10-14 Jinhong Park , Christian Spånslätt , Yuval Gefen , Alexander D. Mirlin

Recent work has extended topological band theory to open, non-Hermitian Hamiltonians, yet little is understood about how non-Hermiticity alters the topological quantization of associated observables. We address this problem by studying the…

Mesoscale and Nanoscale Physics · Physics 2018-10-31 Timothy M. Philip , Mark R. Hirsbrunner , Matthew J. Gilbert