English
Related papers

Related papers: Non-Hermitian systems with a real spectrum and sel…

200 papers

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

Non-Hermitian systems with parity-time symmetry have been found to exhibit real spectra of eigenvalues, indicating a balance between the loss and gain. However, such a balance is not only dependent on the magnitude of loss and gain, but…

Optics · Physics 2020-09-29 Liyou Luo , Jie Luo , Hongchen Chu , Yun Lai

Non-Hermitian systems exhibit anomalous scaling, a striking departure from conventional bulk laws, rooted in the non-Hermitian skin effect (NHSE). Here, we experimentally uncover this scaling and demonstrate its active control in a temporal…

Optics · Physics 2026-03-30 Shulin Wang , Jiawei He , Zhiyuan Yang , Stefano Longhi , Peng Xue

We illuminate the fundamental mechanism responsible for the transition between the non-Hermitian skin effect and defect-induced localization in the bulk. We study a Hamiltonian with non-reciprocal couplings that exhibits the skin effect…

Mesoscale and Nanoscale Physics · Physics 2024-03-20 Bryn Davies , Silvio Barandun , Erik Orvehed Hiltunen , Richard V. Craster , Habib Ammari

The non-Hermitian skin effect is a distinctive phenomenon in non-Hermitian systems, which manifests as the anomalous localization of bulk states at the boundary. To understand the physical origin of the non-Hermitian skin effect, a bulk…

Quantum Physics · Physics 2024-03-06 Tuo Wan , Kai Zhang , Junkai Li , Zhesen Yang , Zhaoju Yang

Zero indirect gaps in band models are typically viewed as unstable and achievable only through fine-tuning. Recent works, however, have revealed robust semimetallic phases in Hermitian systems where the indirect gap remains pinned at zero…

Mesoscale and Nanoscale Physics · Physics 2026-02-10 S Rahul , Giandomenico Palumbo

Alternating current RLC electric circuits form an accessible and highly tunable platform simulating Hermitian as well as non-Hermitian (nH) quantum systems. We propose here a circuit realization of nH Dirac and Weyl Hamiltonians subject to…

Mesoscale and Nanoscale Physics · Physics 2020-02-03 Xiao-Xiao Zhang , Marcel Franz

We consider conditions for the existence of boundary modes in non-Hermitian systems with edges of arbitrary co-dimension. Through a universal formulation of formation criteria for boundary modes in terms of local Green functions, we outline…

Mesoscale and Nanoscale Physics · Physics 2020-02-12 Dan S. Borgnia , Alex Jura Kruchkov , Robert-Jan Slager

We discuss a generalization of the non-Hermitian skin effect to finite-size photonic structures with neither gain nor loss in the bulk and purely real energy spectrum under periodic boundary conditions (PBC). We show that such systems can…

Optics · Physics 2023-10-09 Alexander Poddubny , Janet Zhong , Shanhui Fan

Non-hermiticity presents a vast newly opened territory that harbors new physics and applications such as lasing and sensing. However, only non-Hermitian systems with real eigenenergies are stable, and great efforts have been devoted in…

Other Condensed Matter · Physics 2022-10-25 Russell Yang , Jun Wei Tan , Tommy Tai , Jin Ming Koh , Linhu Li , Stefano Longhi , Ching Hua Lee

Non-Hermitian quantum systems exhibit fascinating characteristics such as non-Hermitian topological phenomena and skin effect, yet their studies are limited by the intrinsic difficulties associated with their eigenvalue problems, especially…

Mesoscale and Nanoscale Physics · Physics 2024-01-23 Guang Yang , Yongkang Li , Yongxu Fu , Zhenduo Wang , Yi Zhang

Non-Hermitian skin effect, the localization of an extensive number of eigenstates at the ends of the system, has greatly expanded the frontier of physical laws. It has long been believed that the present of skin modes is equivalent to the…

Mesoscale and Nanoscale Physics · Physics 2023-04-17 Gang-Feng Guo , Xi-Xi Bao , Han-Jie Zhu , Xiao-Ming Zhao , Lin Zhuang , Lei Tan , Wu-Ming Liu

Non-Hermitian systems with parity-time symmetry have been developed rapidly and hold great promise for future applications. Unlike most existing works considering the symmetry of the free energy terms (e.g., gain-loss system), in this…

Quantum Physics · Physics 2017-11-21 Wenlin Li , Chong Li , Heshan Song

We study how unique features of non-Hermitian lattice systems can be harnessed to improve Hamiltonian parameter estimation in a fully quantum setting. While the so-called non-Hermitian skin effect does not provide any distinct advantage,…

Quantum Physics · Physics 2020-10-26 Alexander McDonald , Aashish A. Clerk

We study the non-Hermitian skin effect in a three-dimensional system of finitely many subwavelength resonators with an imaginary gauge potential. We introduce a discrete approximation of the eigenmodes and eigenfrequencies of the system in…

Analysis of PDEs · Mathematics 2023-11-20 Habib Ammari , Silvio Barandun , Jinghao Cao , Bryn Davies , Erik Orvehed Hiltunen , Ping Liu

We propose a general principle of constructing non-Hermitian (NH) operators for insulating and gapless topological phases in any dimension ($d$) that over an extended NH parameter regime feature real eigenvalues and zero-energy topological…

Mesoscale and Nanoscale Physics · Physics 2026-03-04 Daniel J. Salib , Sanjib Kumar Das , Bitan Roy

We investigate theoretically tunable non-Hermitian skin effect in systems with gain and loss, and find that bipolar (quadripolar) non-Hermitian skin effect characterized by topological invariants in one (two)-dimensional system. We also…

Applied Physics · Physics 2024-10-29 Wen-Cheng Jiang , Hong Wu , Jian Li , Qing-Xu Li , Jia-Ji Zhu

We introduce the notion of pseudo-Hermiticity and show that every Hamiltonian with a real spectrum is pseudo-Hermitian. We point out that all the PT-symmetric non-Hermitian Hamiltonians studied in the literature belong to the class of…

Mathematical Physics · Physics 2016-09-07 Ali Mostafazadeh

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

Non-Hermitian topological insulators have attracted considerable attention due to their distinctive energy band characteristics and promising applications. Here, we systematically investigate non-Hermitian M\"obius insulators and…

Mesoscale and Nanoscale Physics · Physics 2025-06-18 Wenjie Zhang , Yuting Yang , Xiaopeng Shen , Liwei Shi , Zhi Hong Hang