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Related papers: Notes on topological insulators

200 papers

We discuss some aspects of topological invariants that classify topological states of matter with emphasis on topological insulators. The main aspect addressed is if there are only two topological phases to Bloch Hamiltonian that are time…

Strongly Correlated Electrons · Physics 2014-09-05 J. M. Fonseca , V. L. Carvalho-Santos

This work explores the topological properties of altermagnets, a novel class of collinear magnetic materials. We employ equivariant K-theory of magnetic groups and Hamiltonian models to formulate a robust $C^z_4 \mathbb{T}$ topological…

Materials Science · Physics 2025-03-03 Rafael Gonzalez-Hernandez , Higinio Serrano , Bernardo Uribe

We propose to use generic Chern numbers for a characterization of topological insulators. It is suitable for a numerical characterization of low dimensional quantum liquids where strong quantum fluctuations prevent from developing…

Strongly Correlated Electrons · Physics 2009-11-10 Yasuhiro Hatsugai

Topological insulators and D-brane charges in string theory can both be classified by the same family of groups. In this paper, we extend this connection via a geometric transform, giving a novel duality of topological insulators which can…

High Energy Physics - Theory · Physics 2015-11-20 Varghese Mathai , Guo Chuan Thiang

This monograph offers an overview on the topological invariants in fermionic topological insulators from the complex classes. Tools from K-theory and non-commutative geometry are used to define bulk and boundary invariants, to establish the…

Mathematical Physics · Physics 2016-02-17 Emil Prodan , Hermann Schulz-Baldes

We study the topological band theory of time reversal invariant topological insulators and interpret the topological $\mathbb{Z}_2$ invariant as an obstruction in terms of Stiefel--Whitney classes. The band structure of a topological…

Mathematical Physics · Physics 2016-04-12 Ralph M. Kaufmann , Dan Li , Birgit Wehefritz-Kaufmann

We prove the existence of higher-order topological insulators in: {\it i}) fourfold rotoinversion invariant bulk crystals, and {\it ii}) inversion-symmetric systems with or without an additional three-fold rotation symmetry. These states of…

Mesoscale and Nanoscale Physics · Physics 2018-08-22 Guido van Miert , Carmine Ortix

TopologicalNumbers.jl is an open-source Julia package designed to calculate topological invariants, mathematical quantities that characterize the properties of materials in condensed matter physics. These invariants, such as the Chern…

Mesoscale and Nanoscale Physics · Physics 2025-04-29 Keisuke Adachi , Minoru Kanega

Two-dimensional 2-bands insulators breaking time reversal symmetry can present topological phases indexed by a topological invariant called the Chern number. Here we first propose an efficient procedure to determine this topological index.…

Mesoscale and Nanoscale Physics · Physics 2012-05-28 Doru Sticlet , Frederic Piéchon , Jean-Noël Fuchs , Pavel Kalugin , Pascal Simon

The discovery of topological insulators has reformed modern materials science, promising to be a platform for tabletop relativistic physics, electronic transport without scattering, and stable quantum computation. Topological invariants are…

Strongly Correlated Electrons · Physics 2019-08-14 Jorrit Kruthoff , Jan de Boer , Jasper van Wezel

Topological insulators in odd dimensions are characterized by topological numbers. We prove the well-known relation between the topological number given by the Chern character of the Berry curvature and the Chern-Simons level of the low…

High Energy Physics - Theory · Physics 2020-04-15 Hidenori Fukaya , Tetsuya Onogi , Satoshi Yamaguchi , Xi Wu

We study the topological characterization of the energy gaps in general two-dimensional quasiperiodic systems consisting of multiple periodicities, represented by twisted two-dimensional materials. We show that every single gap is uniquely…

Mesoscale and Nanoscale Physics · Physics 2021-09-28 Mikito Koshino , Hiroki Oka

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 present an approach for the calculation of the $\mathbb{Z}_2$ topological invariant in non-crystalline two-dimensional quantum spin Hall insulators. While topological invariants were originally mathematically introduced for crystalline…

Mesoscale and Nanoscale Physics · Physics 2023-02-28 Roberta Favata , Antimo Marrazzo

Topological insulators in odd dimensions are characterized by topological numbers. We prove the well-known relation between the topological number given by the Chern character of the Berry curvature and the Chern-Simons level of the low…

High Energy Physics - Lattice · Physics 2020-03-20 Hidenori Fukaya , Tetsuya Onogi , Satoshi Yamaguchi , Xi Wu

In this paper, we study the magnetic orders of two dimensional correlated topological insulators including the correlated Chern insulator and the correlated Z2 topological insulator at finite temperature. For the 2D correlated Chern…

Strongly Correlated Electrons · Physics 2013-09-24 Ying-Xue Zhu , Jing He , Chun-Li Zang , Ying Liang , Su-Peng Kou

This article is meant as a gentle introduction to the "topological terms" that often play a decisive role in effective theories describing topological quantum effects in condensed matter systems. We first take up several prominent examples,…

Strongly Correlated Electrons · Physics 2015-02-20 Akihiro Tanaka , Shintaro Takayoshi

We explore a large family of one-dimensional (1D) topological crystalline insulators (TCIs) classified by $\mathbb{Z}$ invariants protected by space-time inversion symmetry. This finding stands in marked contrast to the conventional…

Mesoscale and Nanoscale Physics · Physics 2025-07-03 Ling Lin , Yongguan Ke , Chaohong Lee

Topology has appeared in different physical contexts. The most prominent application is topologically protected edge transport in condensed matter physics. The Chern number, the topological invariant of gapped Bloch Hamiltonians, is an…

Mesoscale and Nanoscale Physics · Physics 2018-01-24 Thomas Fösel , Vittorio Peano , Florian Marquardt

Topological invariants are global properties of the ground-state wave function, typically defined as winding numbers in reciprocal space. Over the years, a number of topological markers in real space have been introduced, allowing to map…

Mesoscale and Nanoscale Physics · Physics 2024-01-17 Nicolas Baù , Antimo Marrazzo