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Related papers: Exceptional Non-Hermitian Phases in Disordered Qua…

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Altermagnets (AMs) exhibit vanishing net magnetization but strong momentum-dependent spin splitting enforced by crystal symmetry. Here, we explore the non-Hermitian effects in dissipative two-dimensional AMs. We show that symmetry-compliant…

Mesoscale and Nanoscale Physics · Physics 2026-03-23 Xiao-Ming Zhao , Cui-Xian Guo , Xin-Ran Ma , Xiao-Ran Wang , Su-Peng Kou

The nontrivial degeneracies in non-Hermitian systems, exceptional points (EPs), have attracted extensive attention due to intriguing phenomena. Compared with commonly observed second-order EPs, high-order EPs show rich physics due to their…

Quantum Physics · Physics 2024-12-16 Yue Li , Yang Wu , Yuqi Zhou , Mengxiang Zhang , Xingyu Zhao , Yibo Yuan , Xu Cheng , Yi Li , Xi Qin , Xing Rong , Yiheng Lin , Jiangfeng Du

A fermionic disordered one dimensional wire in the presence of attractive interactions is known to have two distinct phases: A localized and a superconducting one depending on the strength of interaction and disorder. The localized region…

Mesoscale and Nanoscale Physics · Physics 2015-11-18 Richard Berkovits

We study quantum phase coherence and weak localization (WL) in disordered metals with restricted back-scattering and phenomenologically formulate a large class of unconventional transport mechanisms as modified diffusion processes not…

Disordered Systems and Neural Networks · Physics 2010-08-06 Shimul Akhanjee

We present a transmission line theory of exceptional points of degeneracy (EPD) in coupled-mode guiding structures, i.e., a theory that illustrates the characteristics of coupled electromagnetic modes under a special dispersion degeneracy…

Optics · Physics 2017-09-15 Mohamed A. K. Othman , Filippo Capolino

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…

Non-Hermitian Hamiltonians can give rise to exceptional points (EPs) which have been extensively explored with nominally identical coupled resonators. Here a non-Hermitian electromechanical system is developed which hosts vibration modes…

Mesoscale and Nanoscale Physics · Physics 2019-02-06 P. Renault , H. Yamaguchi , I. Mahboob

Exceptional points (EPs), at which more than one eigenvalue and eigenvector coalesce, are unique spectral features of Non-Hermiticity (NH) systems. They exist widely in open systems with complex energy spectra. We experimentally demonstrate…

Dissipation in open systems enriches the possible symmetries of the Hamiltonians beyond the Hermitian framework allowing the possibility of novel non-Hermitian topological phases, which exhibit long-living end states that are protected…

Quantum Physics · Physics 2023-04-05 Wojciech Brzezicki , Matti Silveri , Marcin Płodzień , Francesco Massel , Timo Hyart

Non-Hermitian systems distinguish themselves from Hermitian systems by exhibiting a phase transition point called an exceptional point (EP), which is the point at which two eigenstates coalesce under a system parameter variation. Many…

Mesoscale and Nanoscale Physics · Physics 2016-04-20 Kun Ding , Guancong Ma , Meng Xiao , Z. Q. Zhang , C. T. Chan

We outline a theoretical framework for quantum metrology in non-Hermitian systems, demonstrating both significant failure and exceptional regimes in PT-symmetric Bardeen-Cooper-Schrieffer chains. Through biorthogonal quantum Fisher…

Quantum Physics · Physics 2025-08-08 Harshank Matkar

In order for non-Hermitian (NH) topological effects to be relevant for practical applications, it is necessary to study disordered systems. In the absence of disorder, certain driven-dissipative cavity arrays with engineered non-local…

Mesoscale and Nanoscale Physics · Physics 2023-06-06 Clara C. Wanjura , Matteo Brunelli , Andreas Nunnenkamp

Non-Hermitian (NH) systems, owing to the existence of exceptional point (or ring and surface), exhibit exotic topological features which are inaccessible in Hermitian systems. While current studies on NH topology has primarily focused on…

Quantum Physics · Physics 2026-04-10 Shou-Bang Yang , Pei-Rong Han , Wen Ning , Fan Wu , Zhen-Biao Yang , Shi-Biao Zheng

Non-Hermitian phenomena offer a novel approach to analyze and interpret spectra in the presence of interactions. Using the density-matrix renormalization group (DMRG), we demonstrate the existence of exceptional points for the one-particle…

Strongly Correlated Electrons · Physics 2021-02-08 Roman Rausch , Robert Peters , Tsuneya Yoshida

The interplay of disorder and short finite wire length is the crucial physics hindering progress in the semiconductor-superconductor nanowire platform for realizing non-Abelian Majorana zero modes (MZM). Disorder effectively segments the…

Mesoscale and Nanoscale Physics · Physics 2024-08-05 Haining Pan , Sankar Das Sarma

We show that a composite quantum system described by the tensor product of multiple systems each with a leading-order exceptional point (a non-Hermitian degeneracy at which not only eigenvalues but also eigenstates coalesce) exhibits a…

Quantum Physics · Physics 2025-07-28 Jan Wiersig , Weijian Chen

Exceptional points (EPs) are peculiar band singularities and play a vital role in a rich array of unusual optical phenomena and non-Hermitian band theory. In this paper, we provide a topological classification of isolated EPs based on…

Mesoscale and Nanoscale Physics · Physics 2022-06-29 Haiping Hu , Shikang Sun , Shu Chen

A broad family of phase transitions in the closed as well as open quantum systems is known to be mediated by a non-Hermitian degeneracy (a.k.a. exceptional point, EP) of the Hamiltonian. In the EP limit, in general, the merger of an…

Quantum Physics · Physics 2021-03-16 Miloslav Znojil

Models of disorder with a direction (constant imaginary vector-potential) are considered. These non-Hermitian models can appear as a result of computation for models of statistical physics using transfer matrix technique or describe…

Disordered Systems and Neural Networks · Physics 2009-10-30 K. B. Efetov

Distinct from closed quantum systems, non-Hermitian system can have exceptional points (EPs) where both eigenvalues and eigenvectors coalesce. Recently, it has been proposed and demonstrated that EPs can enhance the performance of sensors…

Quantum Physics · Physics 2019-11-05 Mengzhen Zhang , William Sweeney , Chia Wei Hsu , Lan Yang , A. D. Stone , Liang Jiang