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Related papers: Zero Indirect Band Gap in Non-Hermitian Systems

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The discovery of non-Hermitian skin effect (NHSE) has opened an exciting direction for unveiling unusual physics and phenomena in non-Hermitian system. Despite notable theoretical breakthroughs, actual observation of NHSE's whole…

Materials Science · Physics 2022-12-13 Zhongming Gu , He Gao , Haoran Xue , Jensen Li , Zhongqing Su , Jie Zhu

Non-Hermitian systems have recently attracted broad interest and exhibited intriguing physical phenomena, in which the non-Hermitian skin effect is one of the most remarkable quantum phenomena desiring detailed investigations and has been…

Quantum Physics · Physics 2024-10-08 Mengjie Yang , Luojia Wang , Xiaoxiong Wu , Han Xiao , Danying Yu , Luqi Yuan , Xianfeng Chen

In contrast to Hermitian systems, eigenstates of non-Hermitian ones are in general nonorthogonal. This feature is most pronounced at exceptional points where several eigenstates are linearly dependent. In this work we show that near this…

Quantum Physics · Physics 2016-12-23 Alexander A. Zyablovsky , Evgeny S. Andrianov , Alexander A. Pukhov

We introduce a dissipative lattice gauge model that exhibits the many-body version of the non-Hermitian skin effect. The dissipative couplings between dynamical gauge fields on the lattice links and the surrounding environment generate…

Quantum Physics · Physics 2025-12-29 Yu-Min Hu , Zijian Wang , Biao Lian , Zhong Wang

Non-Hermitian matrices are ubiquitous in the description of nature ranging from classical dissipative systems, including optical, electrical, and mechanical metamaterials, to scattering of waves and open quantum many-body systems. Seminal…

Mesoscale and Nanoscale Physics · Physics 2024-07-08 Kang Yang , Zhi Li , J. Lukas K. König , Lukas Rødland , Marcus Stålhammar , Emil J. Bergholtz

The classification of point gap topology in all local non-Hermitian symmetry classes has been recently established. However, many entries in the resulting periodic table have only been discussed in a formal setting and still lack a physical…

Mesoscale and Nanoscale Physics · Physics 2023-09-04 M. Michael Denner , Titus Neupert , Frank Schindler

Nonhermitian systems provide new avenues to create topological defect states. An unresolved general question is how much the formation of these states depends on asymmetric backscattering, be it nonreciprocal as in the nonhermitian skin…

Optics · Physics 2019-12-04 Martí Bosch , Simon Malzard , Martina Hentschel , Henning Schomerus

Quantum devices characterized by non-Hermitian topology are predicted to show highly robust and potentially useful properties, but realizing them has remained a daunting experimental task. This is because non-Hermiticity is often associated…

The generic nature of band touching points in three-dimensional band structures is at heart of the rich phenomenology, topological stability and novel Fermi arc surface states associated with Weyl semimetals. Here we report on the…

Mesoscale and Nanoscale Physics · Physics 2018-11-13 Johan Carlström , Emil J. Bergholtz

Non-Hermitian skin effect (NHSE) in non-Hermitian lattice systems, associated with a point gap on the complex energy plane, has attracted great theoretical and experimental interest. Much less is studied on the so-called second-order…

Mesoscale and Nanoscale Physics · Physics 2022-08-17 Weiwei Zhu , Jiangbin Gong

The non-Hermitian edge burst is a phenomenon observed in non-Hermitian quantum dynamics, characterized by a significant accumulation of loss at the boundaries of a system. We present an example of the edge burst effect in a lossy lattice…

Quantum Physics · Physics 2025-06-11 G. Sen , C. Yuce

We study non-Hermitian photonic lattices that exhibit competition between conservative and non-Hermitian (gain/loss) couplings. A bipartite sublattice symmetry enforces the existence of non-Hermitian flat bands, which are typically embedded…

Optics · Physics 2017-08-30 Daniel Leykam , Sergej Flach , Y. D. Chong

Non-Hermitian effects have emerged as a new paradigm for the manipulation of phases of matter that profoundly changes our understanding of non-equilibrium systems, introducing novel concepts such as exceptional points and spectral topology,…

Quantum Physics · Physics 2023-12-14 Zhen Li , Li-Wei Wang , Xulong Wang , Zhi-Kang Lin , Guancong Ma , Jian-Hua Jiang

In this work, we demonstrate the presence of an anomalous non-Hermitian skin effects which decay from both ends of a system consisting of two coupled Hermitian chains induced by non-reciprocal inter-chain cross-coupling. Another intriguing…

In non-Hermitian crystals showing the non-Hermitian skin effect, ordinary Bloch band theory and Bloch topological invariants fail to correctly predict energy spectra, topological boundary states, and symmetry breaking phase transitions in…

Quantum Physics · Physics 2019-09-18 Stefano Longhi

We propose an ultracold-atom setting where a fermionic superfluidity with attractive s-wave interaction is uploaded in a non-Hermitian Lieb optical lattice. The existence of a real-energy flat band solution is revealed. We show that the…

Quantum Gases · Physics 2021-05-18 Peng He , Hai-Tao Ding , Shi-Liang Zhu

Non-Hermitian skin effect and critical skin effect are unique features of non-Hermitian systems. In this Letter, we study an open system with its dynamics of single-particle correlation function effectively dominated by a non-Hermitian…

Mesoscale and Nanoscale Physics · Physics 2020-11-04 Chun-Hui Liu , Kai Zhang , Zhesen Yang , Shu Chen

The skin effect and topological edge states in non-Hermitian system have been well-studied, and the second-order skin effect and corner modes have also been proposed in non-Hermitian system recently. In this paper, we construct the nested…

Mesoscale and Nanoscale Physics · Physics 2021-01-27 Yongxu Fu , Jihan Hu , Shaolong Wan

We analyze the guided modes in coupled waveguides made of negative-index materials without gain or loss. We show that it supports non-Hermitian phenomenon on the existence of guided mode versus geometric parameters of the structure. The…

Optics · Physics 2023-04-26 Li-Ting Wu , Xin-Zhe Zhang , Ru-Zhi Luo , Jing Chen

We explore band structures of one-dimensional open systems described by periodic non-Hermitian operators, based on continuum models and tight-binding models. We show that imaginary scalar potentials do not open band gaps but instead lead to…

Quantum Physics · Physics 2025-01-10 Ken Mochizuki , Tomoki Ozawa