English
Related papers

Related papers: Topological Euler insulators

200 papers

This paper reports on the experimental observation of topologically protected edge state and exceptional point in an open and Non-Hermitian system. While the theoretical underpinning is generic to wave physics, the simulations and…

Mesoscale and Nanoscale Physics · Physics 2018-09-26 Weiwei Zhu , Xinsheng Fang , Dongting Li , Yong Sun , Yong Li , Yun Jing , Hong Chen

A topological insulator is classically modeled as an isotropic dielectric-magnetic with a magnetoelectric pseudoscalar $\Psi$ existing in its bulk while its surface is charge-free and current-free. An alternative model is obtained by…

Optics · Physics 2017-07-06 Akhlesh Lakhtakia , Tom G. Mackay

An important characteristic of topological band insulators is the necessary presence of in-gap edge states on the sample boundary. We utilize this fact to show that when the boundary is reconnected with a twist, there are always zero-energy…

Strongly Correlated Electrons · Physics 2009-11-13 Dung-Hai Lee , Guang-Ming Zhang , Tao Xiang

This paper proposes a quantitative description of the low energy edge states at the interface between two-dimensional topological insulators. They are modeled by continuous Hamiltonians as systems of Dirac equations that are amenable to a…

Mathematical Physics · Physics 2018-08-16 Guillaume Bal

We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger (SSH) model with long-range hopping terms. By computing the quantum geometry tensor, we derive exactly expressions for the quantum…

Strongly Correlated Electrons · Physics 2024-04-15 Xiang-Long Zeng , Wen-Xi Lai , Yi-Wen Wei , Yu-Quan Ma

We discuss recent advances in the study of topological insulators protected by spatial symmetries by reviewing three representative, theoretical examples. In three dimensions, these states of matter are generally characterized by the…

Mesoscale and Nanoscale Physics · Physics 2019-06-12 Alexander Lau , Carmine Ortix

Topological insulators are transformative quantum solids with immune-to-disorder metallic surface states having Dirac band structure. Ubiquitous charged bulk defects, however, pull the Fermi energy into the bulk bands, denying access to…

The discovery that the band structure of electronic insulators may be topologically non-trivial has unveiled distinct phases of electronic matter with novel properties. Recently, mechanical lattices have been found to have similarly rich…

Mesoscale and Nanoscale Physics · Physics 2018-10-10 Noah P. Mitchell , Lisa M. Nash , Daniel Hexner , Ari Turner , William T. M. Irvine

After the classification of topological states of matter has been clarified for non-interacting electron systems, the theoretical connection between gapless boundary modes and nontrivial bulk topological structures, and their evolutions as…

Strongly Correlated Electrons · Physics 2018-08-15 M. Sasaki , A. Ohnishi , Nabyendu Das , K. -S. Kim , Heon-Jung Kim

We study continuations of topological edge states in the Su-Schrieffer-Heeger model with on-site cubic (Kerr) nonlinearity, which is a 1D nonlinear photonic topological insulator (TI). Based on the topology of the underlying spatial…

Pattern Formation and Solitons · Physics 2021-12-28 Y. -P. Ma , H. Susanto

The surface of a 3D topological insulator is described by a helical electron state with the electron's spin and momentum locked together. We show that in the presence of ferromagnetic fluctuations the surface of a topological insulator is…

Strongly Correlated Electrons · Physics 2016-08-16 Mehdi Kargarian , Dmitry K. Efimkin , Victor Galitski

We demonstrate theoretically an atomic liquid phase that supports topologically nontrivial electronic structure. A minimum two-orbital model of liquid topological insulator in two dimensions is constructed within the framework of…

Mesoscale and Nanoscale Physics · Physics 2019-06-07 Gia-Wei Chern

Topological phase transitions are typically characterized by abrupt changes in a quantized invariant. Here we report a contrasting paradigm in non-Hermitian parity-time symmetric systems, where the topological invariant remains conserved,…

Mesoscale and Nanoscale Physics · Physics 2025-03-31 Kang Yang , Zhi Li , Peng Xue , Emil J. Bergholtz , Piet W. Brouwer

We define a class of insulators with gapless surface states protected from localization due to the statistical properties of a disordered ensemble, namely due to the ensemble's invariance under a certain symmetry. We show that these…

Mesoscale and Nanoscale Physics · Physics 2014-04-23 I. C. Fulga , B. van Heck , J. M. Edge , A. R. Akhmerov

A higher order topological insulator is an extended notion of the conventional topological insulator, which belongs to a special class of topological insulators where the conventional bulk-boundary correspondence is not applicable. The bulk…

Mesoscale and Nanoscale Physics · Physics 2018-07-24 Motohiko Ezawa

We show that edge states similar to those known for topological insulators exist in two-dimensional electron system with one-band spectrum in the presence of heterogeneous spin-orbit interaction (SOI). These states appear at boundaries…

Mesoscale and Nanoscale Physics · Physics 2010-11-17 Aleksei A. Sukhanov , Vladimir A. Sablikov

According to the mathematical classification of topological band structures, there exist a number of fascinating topological states in dimensions larger than three with exotic boundary phenomena and interesting topological responses. While…

Mesoscale and Nanoscale Physics · Physics 2020-05-13 Rui Yu , Y. X. Zhao , Andreas P. Schnyder

A salient feature of solid-state topological materials in two dimensions is the presence of conducting electronic edge states that are insensitive to scattering by disorder. Such unidirectional edge states have been explored in many…

Optics · Physics 2021-12-28 Sebabrata Mukherjee , Mikael C. Rechtsman

Topological insulators and their intriguing edge states can be understood in a single-particle picture and can as such be exhaustively classified. Interactions significantly complicate this picture and can lead to entirely new insulating…

Strongly Correlated Electrons · Physics 2013-09-10 Emil J. Bergholtz , Zhao Liu

Topological phases of matter have been extensively studied for their intriguing bulk and edge properties. Recently, higher-order topological insulators with boundary states that are two or more dimensions lower than the bulk states, have…

Mesoscale and Nanoscale Physics · Physics 2020-01-08 Xiujuan Zhang , Bi-Ye Xie , Hong-Fei Wang , Xiangyuan Xu , Yuan Tian , Jian-Hua Jiang , Ming-Hui Lu , Yan-Feng Chen