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

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We show that non-Hermitian engineering can play a positive role in quantum systems. This is in contrast to the widely accepted notion that optical losses are a foe that must be eliminated or, at least, minimized. We take advantage of the…

Quantum Physics · Physics 2019-12-19 Nicolás Quesada , Eugene Adjei , Ramy El-Ganainy , Agata M. Brańczyk

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

In some non-Hermitian systems, the eigenstates in the bulk are localized at the boundaries of the systems. This is called the non-Hermitian skin effect, and it has been studied mostly in discrete systems. In the present work, we study the…

Mesoscale and Nanoscale Physics · Physics 2022-05-09 Kazuki Yokomizo , Taiki Yoda , Shuichi Murakami

We demonstrate that crystal defects can act as a probe of intrinsic non-Hermitian topology. In particular, in point-gapped systems with periodic boundary conditions, a pair of dislocations may induce a non-Hermitian skin effect, where an…

Mesoscale and Nanoscale Physics · Physics 2021-10-13 Frank Schindler , Abhinav Prem

Robust boundary states epitomize how deep physics can give rise to concrete experimental signatures with technological promise. Of late, much attention has focused on two distinct mechanisms for boundary robustness - topological protection,…

Mesoscale and Nanoscale Physics · Physics 2021-12-30 Deyuan Zou , Tian Chen , Wenjing He , Jiacheng Bao , Ching Hua Lee , Houjun Sun , Xiangdong Zhang

The energy band attraction (EBA) caused by the non-orthogonal eigenvectors is a unique phenomenon in the non-Hermitian (NH) system. However, restricted by the required tight-binding approximation and meticulously engineered complex…

Mesoscale and Nanoscale Physics · Physics 2020-09-30 Maopeng Wu , Ruiguang Peng , Jingquan Liu , Qian Zhao , Ji Zhou

We study non-Hermitian spatial symmetries -- a class of symmetries that have no counterparts in Hermitian systems -- and study how normal and exceptional semimetals can be stabilized by these symmetries. Different from internal ones,…

Mesoscale and Nanoscale Physics · Physics 2022-06-03 W. B. Rui , Zhen Zheng , Chenjie Wang , Z. D. Wang

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 non-Hermitian skin effect describes the concentration of an extensive number of eigenstates near the boundaries of certain dissipative systems. This phenomenon has raised a huge interest in different areas of physics, including…

Optics · Physics 2025-04-10 Stefano Longhi

We report the exact closed-form solutions for higher-order topological states as well as explicit energy-spectrum relationships in two-dimensional (2D) non-Hermitian multi-orbital lattices with generalized boundary conditions. These…

Due to the fundamental position of spin-orbit coupled ultracold atoms in the simulation of topological insulators, the gain/loss effects on these systems should be evaluated when considering the measurement or the coupling to the…

Quantum Gases · Physics 2022-06-20 Zhi-Cong Xu , Ziyu Zhou , Enhong Cheng , Li-Jun Lang , Shi-Liang Zhu

Non-reciprocal lattice systems are among the simplest non-Hermitian systems, exhibiting several key features absent in their Hermitian counterparts. In this study, we investigate the Hatano-Nelson model with impurity and unveil how the…

Quantum Physics · Physics 2025-09-11 Nico G. Leumer , Dario Bercioux

Non-Hermitian systems, which contain gain or loss, commonly host exceptional point degeneracies rather than the diabolic points found in Hermitian systems. We present a class of non-Hermitian lattice models with symmetry-stabilized diabolic…

Mesoscale and Nanoscale Physics · Physics 2020-06-17 Haoran Xue , Qiang Wang , Baile Zhang , Y. D. Chong

We study a non-Hermitian extension of the Creutz ladder with generic non-reciprocal hopping. By mapping the ladder onto two decoupled non-Hermitian Su--Schrieffer--Heeger (SSH) chains, we uncover a rich structure in parameter space under…

Quantum Physics · Physics 2025-12-24 Debashish Dutta , Sayan Choudhury

When waves impinge on a disordered material they are back-scattered and form a highly complex interference pattern. Suppressing any such distortions in the free propagation of a wave is a challenging task with many applications in a number…

Recently, synthetic spin-orbit coupling has been introduced into cold-atom systems for more flexible control of the Hamiltonian, which was further made time-varying through two-photon detuning to achieve dynamic control of the cold-atom…

Quantum Physics · Physics 2024-03-05 Dong Liu , Zejian Ren , Wai Chun Wong , Entong Zhao , Chengdong He , Ka Kwan Pak , Gyu-Boong Jo , Jensen Li

Utilizing scattering theory, we quantify the consequences of physical constraints that limit the visibility of non-Hermitian effects in passive devices. The constraints arise from the fundamental requirement that the system obeys causality,…

Optics · Physics 2023-12-15 Henning Schomerus

It has recently been shown that the non-Hermitian skin effect can be suppressed by magnetic fields. In this work, using a two-dimensional tight-binding lattice, we demonstrate that a pseudomagnetic field can also lead to the suppression of…

Mesoscale and Nanoscale Physics · Physics 2024-06-18 Hau Tian Teo , Subhaskar Mandal , Yang Long , Haoran Xue , Baile Zhang

Diamond is studied by path integral molecular dynamics simulations of the atomic nuclei in combination with a tight-binding Hamiltonian to describe its electronic structure and total energy. This approach allows us to quantify the influence…

Materials Science · Physics 2009-11-11 Rafael Ramirez , Carlos P. Herrero , Eduardo R. Hernandez

An imaginary gauge transformation is at the core of the non-Hermitian skin effect. Here we show that such a transformation can be performed in momentum space as well, which reveals that certain gain and loss modulated systems in their…

Quantum Physics · Physics 2022-12-21 Jose H. D. Rivero , Liang Feng , Li Ge