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Related papers: Non-Hermitian boundary spectral winding

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Unlike their Hermitian counterparts, non-Hermitian (NH) systems may display an exponential sensitivity to boundary conditions and an extensive number of edge-localized states in systems with open boundaries, a phenomena dubbed the…

Disordered Systems and Neural Networks · Physics 2021-04-14 Jahan Claes , Taylor L. Hughes

Unlike Hermitian systems, non-Hermitian energy spectra under periodic boundary conditions can form closed loops in the complex energy plane, a phenomenon known as point gap topology. In this paper, we investigate the self-intersection…

Quantum Physics · Physics 2025-04-11 Jinghui Pi , Chenyang Wang , Yong-Chun Liu , Yangqian Yan

Non-Hermiticity gives rise to unique topological phases without Hermitian analogs. However, the effective field theory has yet to be established. Here, we develop a field-theoretical description of the intrinsic non-Hermitian topological…

Mesoscale and Nanoscale Physics · Physics 2021-06-01 Kohei Kawabata , Ken Shiozaki , Shinsei Ryu

Asymmetrically directed couplings in non-Hermitian systems cause directional amplification that leads to boundary skin state accumulation. However, counter-intuitively, the direction of accumulation may not follow that of the directed…

Quantum Physics · Physics 2025-09-05 Mengjie Yang , Ching Hua Lee

Recently, it has been revealed that a variety of novel phenomena emerge in hyperbolic spaces, while non-Hermitian physics has significantly enriched the landscape of condensed matter physics. Building on these developments, we construct a…

Other Condensed Matter · Physics 2024-10-22 Ruizhe Shen , Wei Jie Chan , Ching Hua Lee

We unveil an unexpected non-Hermitian phenomenon, dubbed edge burst, in non-Hermitian quantum dynamics. Specifically, in a class of non-Hermitian quantum walk in periodic lattices with open boundary condition, an exceptionally large portion…

Quantum Physics · Physics 2022-03-25 Wen-Tan Xue , Yu-Min Hu , Fei Song , Zhong Wang

The topology of non-Hermitian systems is drastically shaped by the non-Hermitian skin effect, which leads to the generalized bulk-boundary correspondence and non-Bloch band theory. The essential part in formulations of bulk-boundary…

Mesoscale and Nanoscale Physics · Physics 2019-12-11 Fei Song , Shunyu Yao , Zhong Wang

Non-Hermiticity naturally breaks down the adiabaticity and thus leads to non-Abelian behaviors in multi-band systems. Here, we study how non-Abelian properties emerge in non-Hermitian systems by considering a multi-band non-Hermitian model…

Mesoscale and Nanoscale Physics · Physics 2025-09-17 Ziyu Zhou , Zhi-Cong Xu , Li-Jun Lang

The bulk-boundary or bulk-edge correspondence is a principle relating surface confined states to the topological classification of the bulk. By combining non-Hermitian ingredients in terms of gain or loss with media that violate…

Mesoscale and Nanoscale Physics · Physics 2020-11-18 Penglin Gao , Morten Willatzen , Johan Christensen

Spectra of bulk or edges in topological insulators are often made complex by non-Hermiticity. Here, we show that symmetry protection enables entirely real spectra for both bulk and edges even in non-Hermitian topological insulators. In…

Mesoscale and Nanoscale Physics · Physics 2020-09-11 Kohei Kawabata , Masatoshi Sato

The spectral properties of a non-Hermitian quasi-1D lattice in two of the possible dimerization configurations are investigated. Specifically, it focuses on a non-Hermitian diamond chain that presents a zero-energy flat band. The flat band…

Mesoscale and Nanoscale Physics · Physics 2023-12-19 C. Martínez-Strasser , M. A. J. Herrera , A. García-Etxarri , G. Palumbo , F. K. Kunst , D. Bercioux

We show that anomalous Floquet topological insulators generate intrinsic, non-Hermitian topology on their boundary. As a consequence, removing a boundary hopping from the time-evolution operator stops the propagation of chiral edge modes,…

Mesoscale and Nanoscale Physics · Physics 2024-09-26 Hui Liu , Ion Cosma Fulga

The non-Hermitian skin effect (NHSE) undermines the conventional bulk-boundary correspondence (BBC) since it results in a distinct bulk spectrum in open-boundary systems compared to the periodic counterpart. Using the non-Hermitian (NH)…

Mesoscale and Nanoscale Physics · Physics 2024-05-03 Yi-Xin Xiao , Zhao-Qing Zhang , C. T. Chan

We report a novel localization phenomenon that emerges in non-Hermitian and quasiperiodic coupled systems, which we dub ``Anderson-Skin (AS) dualism". The emergence of AS dualism is due to the fact that non-Hermitian topological systems…

Disordered Systems and Neural Networks · Physics 2025-11-18 Shan-Zhong Li , Linhu Li , Shi-Liang Zhu , Zhi Li

We consider a 3-dimensional (3D) non-Hermitian exceptional line semimetal model and take open boundary conditions in x, y, and z directions separately. In each case, we calculate the parameter regions where the bulk-boundary correspondence…

Mesoscale and Nanoscale Physics · Physics 2020-10-22 Zhicheng Zhang , Zhesen Yang , Jiangping Hu

The discovery of the non-Hermitian skin effect (NHSE) has revolutionized our understanding of wave propagation in non-Hermitian systems, highlighting unexpected localization effects beyond conventional theories. Here, we discover that NHSE,…

Optics · Physics 2024-11-14 Ningxin Kong , Chenghe Yu , Yilun Xu , Matteo Fadel , Xinyao Huang , Qiongyi He

Topological materials exhibit edge-localized scattering-free modes protected by their nontrivial bulk topology through the bulk-edge correspondence in Hermitian systems. While topological phenomena have recently been much investigated in…

Mesoscale and Nanoscale Physics · Physics 2020-11-16 Kazuki Sone , Yuto Ashida , Takahiro Sagawa

Open systems feature a variety of phenomena that arise from non-Hermitian physics. Recent theoretical studies have offered much insights into these phenomena through the non-Bloch band theory, though many of the theory's key features are…

Quantum Physics · Physics 2025-11-11 Mu Yang , Yue Li , Mingtao Xu , Wei Yi , Jin-Shi Xu , Chuan-Feng Li , Guang-Can Guo

A non-Hermitian topological insulator is fundamentally different from conventional topological insulators. The non-Hermitian skin effect arises in a nonreciprocal tight binding lattice with open edges. In this case, not only topological…

Mesoscale and Nanoscale Physics · Physics 2020-01-01 C. Yuce

We investigate a one-dimensional superconducting lattice that realizes all internal symmetries permitted in non-Hermitian systems, characterized by nonreciprocal hopping, onsite dissipation, and $s$-wave singlet pairing in a…

Mesoscale and Nanoscale Physics · Physics 2026-02-19 Chuo-Kai Chang , Kazuma Saito , Nobuyuki Okuma , Hsien-Chung Kao , Chen-Hsuan Hsu