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Related papers: Topological classification of non-Hermitian bands

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We present a study of complex energy braiding in a 1D non-Hermitian system with $n$th order long range asymmetrical coupling. Our work highlights the emergence of novel topological phenomena in such systems beyond the conventional…

Quantum Physics · Physics 2024-07-08 S. M. Rafi-Ul-Islam , Zhuo Bin Siu , Md. Saddam Hossain Razo , Mansoor B. A. Jalil

The statistical mechanical approach to complex networks is the dominant paradigm in describing natural and societal complex systems. The study of network properties, and their implications on dynamical processes, mostly focus on locally…

Statistical Mechanics · Physics 2013-06-27 Giovanni Petri , Martina Scolamiero , Irene Donato , Francesco Vaccarino

Degeneracy points in non-Hermitian systems are of great interest. While a homotopic framework exists for understanding their behavior in the absence of symmetry, it does not apply to symmetry-protected degeneracy points with reduced…

Mesoscale and Nanoscale Physics · Physics 2024-06-12 Jia-Zheng Li , Kai Bai , Cheng Guo , Tian-Rui Liu , Liang Fang , Duanduan Wan , Meng Xiao

The fundamental concept underlying topological phenomena posits the geometric phase associated with eigenstates. In contrast to this prevailing notion, theoretical studies on time-varying Hamiltonians allow for a new type of topological…

Quantum Physics · Physics 2025-11-27 Pengfei Lu , Yang Liu , Qifeng Lao , Teng Liu , Xinxin Rao , Ji Bian , Hao Wu , Feng Zhu , Le Luo

Knots and links represent a fundamental motif of non-local connectivity that permeates the physical sciences from string theory to protein folds. While spectral braiding has been explored in two-band non-Hermitian models across various…

Quantum Physics · Physics 2026-04-30 Truman Yu Ng , Yuzhu Wang , Wei Jie Chan , Ruizhe Shen , Tianqi Chen , Ching Hua Lee

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

Braiding is a geometric concept that manifests itself in a variety of scientific contexts from biology to physics, and has been employed to classify bulk band topology in topological materials. Topological edge states can also form braiding…

Mesoscale and Nanoscale Physics · Physics 2024-07-10 Yang Long , Zihao Wang , Chen Zhang , Haoran Xue , Yuxin Zhao , Baile Zhang

Quasi-particles described by Green's functions of equilibrium systems exhibit non-Hermitian topological phenomena because of their finite lifetime. This non-Hermitian perspective on equilibrium systems provides new insights into correlated…

Strongly Correlated Electrons · Physics 2020-07-28 Tsuneya Yoshida , Robert Peters , Norio Kawakami , Yasuhiro Hatsugai

Topological phases of matter are classified based on their Hermitian Hamiltonians, whose real-valued dispersions together with orthogonal eigenstates form nontrivial topology. In the recently discovered higher-order topological insulators…

Mesoscale and Nanoscale Physics · Physics 2021-03-31 He Gao , Haoran Xue , Zhongming Gu , Tuo Liu , Jie Zhu , Baile Zhang

As energy dissipation and gain are ubiquitous in the real world, such phenomena demand the generalization of Hermitian methods such as the analysis of topological properties for non-Hermitian systems. However, as non-Hermitian systems…

Mesoscale and Nanoscale Physics · Physics 2026-02-02 Cameron Gibson , Evelyn Tang

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 nature of complex eigenenergy enables unique band topology to the non-Hermitian (NH) lattice systems. Recently, there has been a fast growing interest in the elusive winding and braiding topologies of the NH single and double bands,…

Mesoscale and Nanoscale Physics · Physics 2022-12-16 Qicheng Zhang , Luekai Zhao , Xun Liu , Xiling Feng , Liwei Xiong , Wenquan Wu , Chunyin Qiu

Non-Hermitian systems exhibit richer topological properties compared to their Hermitian counterparts. It is well known that non-Hermitian systems have been classified based on either the symmetry relations for non-Hermitian Hamiltonians or…

Mesoscale and Nanoscale Physics · Physics 2024-06-11 Zhiyu Jiang , Ryo Okamoto , Hideaki Obuse

Recent years have seen a growing interest in topological phases beyond the standard paradigm of gapped, isolated systems. One recent direction is to explore topological features in non-hermitian systems that are commonly used as effective…

Mesoscale and Nanoscale Physics · Physics 2026-02-03 Carlos Ortega-Taberner , Maria Hermanns

We establish non-Hermitian topological mechanics in one dimensional (1D) and two dimensional (2D) lattices consisting of mass points connected by meta-beams that lead to odd elasticity. Extended from the "non-Hermitian skin effect" in 1D…

Soft Condensed Matter · Physics 2020-05-19 Di Zhou , Junyi Zhang

Coupled oscillator networks show a complex interrelations between topological characteristics of the network and the nonlinear stability of single nodes with respect to large but realistic perturbations. We extend previous results on these…

Chaotic Dynamics · Physics 2017-04-05 Jan Nitzbon , Paul Schultz , Jobst Heitzig , Jürgen Kurths , Frank Hellmann

We classify insulators by generalized symmetries that combine space-time transformations with quasimomentum translations. Our group-cohomological classification generalizes the nonsymmorphic space groups, which extend point groups by…

Mesoscale and Nanoscale Physics · Physics 2016-04-18 A. Alexandradinata , Zhijun Wang , B. Andrei Bernevig

The effect of non-Hermiticity in band topology has sparked many discussions on non-Hermitian topological physics. It has long been known that non-Hermitian Hamiltonians can exhibit real energy spectra under the condition of parity-time…

Mesoscale and Nanoscale Physics · Physics 2024-03-20 Yang Long , Haoran Xue , Baile Zhang

The topological band theory predicts that bulk materials with nontrivial topological phases support topological edge states. This phenomenon is universal for various wave systems and has been widely observed for electromagnetic and acoustic…

Mesoscale and Nanoscale Physics · Physics 2021-07-14 Hao Hu , Song Han , Yihao Yang , Dongjue Liu , Haoran Xue , Gui-Geng Liu , Zheyu Cheng , Qi Jie Wang , Shuang Zhang , Baile Zhang , Yu Luo

Non-Hermitian systems exhibit interesting band structures, where novel topological phenomena arise from the existence of exceptional points at which eigenvalues and eigenvectors coalesce. One important open question is how this would…

Mesoscale and Nanoscale Physics · Physics 2023-10-20 Marcus Stålhammar , Cristiane Morais Smith