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Related papers: A New Numerical Method for $\mathbb{Z}_2$ Topologi…

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Effects of disorder on two-dimensional Z2 topological insulator are studied numerically by the transfer matrix method. Based on the scaling analysis, the phase diagram is derived for a model of HgTe quantum well as a function of disorder…

Mesoscale and Nanoscale Physics · Physics 2011-05-10 Ai Yamakage , Kentaro Nomura , Ken-Ichiro Imura , Yoshio Kuramoto

A remarkable discovery in recent years is that there exist various kinds of topological insulators and superconductors characterized by a periodic table according to the system symmetry and dimensionality. To physically realize these…

Mesoscale and Nanoscale Physics · Physics 2014-02-24 Dong-Ling Deng , Sheng-Tao Wang , Lu-Ming Duan

Many magnetic point-group symmetries induce a topological classification on crystalline insulators, dividing them into those that have a nonzero quantized Chern-Simons magnetoelectric coupling ("axion-odd" or "topological"), and those that…

Mesoscale and Nanoscale Physics · Physics 2020-04-29 Nicodemos Varnava , Ivo Souza , David Vanderbilt

The aim of this series of two papers is to discuss topological invariants for interacting topological insulators (TIs). In the first paper (I), we provide a paradigm of efficient numerical evaluation scheme for topological invariants, in…

Strongly Correlated Electrons · Physics 2016-06-08 Yuan-Yao He , Han-Qing Wu , Zi Yang Meng , Zhong-Yi Lu

We introduce the electronic polarization originally defined in one-dimensional lattice systems to characterize two-dimensional topological insulators. The main idea is to use spiral boundary conditions which sweep all lattice sites in…

Strongly Correlated Electrons · Physics 2021-11-12 Masaaki Nakamura , Shohei Masuda , Satoshi Nishimoto

Topological insulators are exotic material that possess conducting surface states protected by the topology of the system. They can be classified in terms of their properties under discrete symmetries and are characterized by topological…

Quantum Gases · Physics 2019-05-29 M. Mochol-Grzelak , A. Dauphin , A. Celi , M. Lewenstein

An exhaustive classification scheme of topological insulators and superconductors is presented. The key property of topological insulators (superconductors) is the appearance of gapless degrees of freedom at the interface/boundary between a…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Andreas P. Schnyder , Shinsei Ryu , Akira Furusaki , Andreas W. W. Ludwig

We define a new $Z_2$-valued index to characterize the topological properties of periodically driven two dimensional crystals when the time-reversal symmetry is enforced. This index is associated with a spectral gap of the evolution…

Mesoscale and Nanoscale Physics · Physics 2015-03-24 David Carpentier , Pierre Delplace , Michel Fruchart , Krzysztof Gawędzki

Symmetry indicators have proven to be extremely helpful in identifying topologically non-trivial crystalline insulators using symmetry-group representations of their Bloch states. An extension of this approach to superconducting systems…

Superconductivity · Physics 2020-01-29 Anastasiia Skurativska , Titus Neupert , Mark H Fischer

We investigate a tight-binding model of the octahedron-decorated cubic lattice with spin-orbit coupling. We calculate the band structure of the lattice and evaluate the Z_2 topological indices. According to the Z_2 topological indices and…

Strongly Correlated Electrons · Physics 2015-05-27 Jing-Min Hou , Wen-Xin Zhang , Guo-Xiang Wang

In this paper, we formulate the real-space Chern number in a supercell framework. In this framework, the overlap matrix between two corners of the Brillouin zone (BZ) is derived from diagonalizing the real-space Hamiltonian with periodic…

Mesoscale and Nanoscale Physics · Physics 2026-04-15 Kiminori Hattori , Shinji Nakata

We identify a topological Z index for three dimensional chiral insulators with P*T symmetry where two Hamiltonian terms define a nodal loop. Such systems may belong in the AIII or DIII symmetry class. The Z invariant is a winding number…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 Linhu Li , Chuanhao Yin , Shu Chen , Miguel A. N. Araújo

Identification of a non-trivial $\mathbb{Z}_{2}$ index in a spinful two dimensional insulator indicates the presence of an odd, quantized (pseudo)spin-resolved Chern number, $C_{s}=(C_{\uparrow}-C_{\downarrow})/2$. However, the statement is…

Materials Science · Physics 2024-06-19 Alexander C. Tyner

We study topological indices of Fermionic time-reversal invariant topological insulators in two dimensions, in the regime of strong Anderson localization. We devise a method to interpolate between certain Fredholm operators arising in the…

Mathematical Physics · Physics 2022-11-30 Alex Bols , Jeffrey Schenker , Jacob Shapiro

Kondo insulators are particularly simple type of heavy electron material, where a filled band of heavy quasiparticles gives rise to a narrow band insulator. Starting with the Anderson lattice Hamiltonian, we develop a topological…

Strongly Correlated Electrons · Physics 2013-05-29 Maxim Dzero , Kai Sun , Victor Galitski , Piers Coleman

We introduce the topologically twisted index for four-dimensional $\mathcal N=1$ gauge theories quantized on ${\rm AdS}_2 \times S^1$. We compute the index by applying supersymmetric localization to partition functions of vector and chiral…

High Energy Physics - Theory · Physics 2023-07-24 Daniele Iannotti , Antonio Pittelli

Algebraic and geometric mean density of states in disordered systems may reveal properties of electronic localization. In order to understand the topological phases with disorder in two dimensions, we present the calculated density of…

Mesoscale and Nanoscale Physics · Physics 2013-12-02 Yan-Yang Zhang , Shun-Qing Shen

We use a "monodromy" argument to derive new expressions for the ${\bm Z}_2$ invariants of topological insulators with time-reversal symmetry in 2 and 3 dimensions. The derivations and the final expressions do not require any gauge choice…

Materials Science · Physics 2011-06-10 Emil Prodan

The atomic-scale influence of disorder on the topological order can be quantified by a universal topological marker, although the practical calculation of the marker becomes numerically very costly in higher dimensions. We propose that for…

Disordered Systems and Neural Networks · Physics 2026-02-09 Ranadeep Roy , Wei Chen

Topological insulators can be characterized alternatively in terms of bulk or edge properties. We prove the equivalence between the two descriptions for two-dimensional solids in the single-particle picture. We give a new formulation of the…

Mathematical Physics · Physics 2015-06-05 G. M. Graf , M. Porta