English
Related papers

Related papers: Non-Markovian Quantum Exceptional Points

200 papers

Dynamical encirclement of an Exceptional Point (EP) and corresponding time-asymmetric mode evolution properties due to breakdown in adiabatic theorem have been a key to range of exotic physical effects in various open atomic, molecular and…

Optics · Physics 2019-04-17 Arnab Laha , Sibnath Dey , Harsh K. Gandhi , Abhijit Biswas , Somnath Ghosh

Exceptional points (EPs) exhibit strongly enhanced spectral responses and are therefore promising candidates for sensing applications. Whether these non-Hermitian degeneracies provide a genuine advantage in the quantum regime has been the…

Quantum Physics · Physics 2026-03-12 Jan Wiersig , Stefan Rotter

The physics of systems that cannot be described by a Hermitian Hamiltonian, has been attracting a great deal of attention in recent years, motivated by their nontrivial responses and by a plethora of applications for sensing, lasing, energy…

Optics · Physics 2021-03-16 Alex Krasnok , Nikita Nefedkin , Andrea Alu

Exceptional points (EPs) are non-Hermitian degeneracies, where both eigenvalues and eigenvectors coalesce, which are fundamentally distinct from their Hermitian counterparts. In this study, we investigate the influence of hexagonal warping…

Mesoscale and Nanoscale Physics · Physics 2026-01-13 Md Afsar Reja , Awadhesh Narayan

There has been debate around applicability of exceptional points (EP) for quantum sensing. To resolve this, we first explore how to experimentally implement the nonhermitian non-diagonalizable Hamiltonians, that exhibit EPs, in quantum…

Quantum Physics · Physics 2024-01-15 Chetan Waghela , Shubhrangshu Dasgupta

The emergence of exceptional points (EPs) in the parameter space of a non-hermitian (2D) eigenvalue problem is studied in a general sense in mathematical physics, and has in the last decade successively reached the scope of experiments. In…

One of the most fascinating and puzzling aspects of non-Hermitian systems is their spectral degeneracies, i.e., exceptional points (EPs), at which both eigenvalues and eigenvectors coalesce to form a defective state space. While coupled…

Mesoscale and Nanoscale Physics · Physics 2023-03-08 Kuangyin Deng , Xin Li , Benedetta Flebus

Higher-order exceptional points (EPs) in non-Hermitian systems showcase diverse physical phenomena but require more parameter space freedom or symmetries. It leads to a challenge for the exploration of high-order EP geometries in…

Quantum Physics · Physics 2025-10-22 Hao Chen , Xiao Qin , Jian-Jun Dong , Yu-Yu Zhang , Zi-Xiang Hu

Controlling gain and loss of coupled optical cavities can induce non-Hermitian degeneracies of eigenstates, called exceptional points (EPs). Various unconventional phenomena around EPs have been reported, and expected to incorporate extra…

We construct a theory to introduce the concept of topologically robust exceptional points (EP). Starting from an ordered system with $N$ elements, we find the necessary condition to have the highest order exceptional point, namely…

Optics · Physics 2018-12-07 Cem Yuce , Hamidreza Ramezani

Compared with Hermitian theory, non-Hermitian physics offers a fundamentally different mathematical framework, enabling the observation of topological phenomena that have no analogue in Hermitian systems. Among these, the exceptional point…

Quantum Physics · Physics 2025-09-24 Zhong-Sheng Chen , Wei-Xin Chen , Fan Wu , Zhong-Wei Xu , Jing Ma , Yun-Kun Jiang , Huai-Zhi Wu , Shi-Biao Zheng

Exceptional points (EPs) in anti-parity-time (APT)-symmetric systems have attracted significant interest. While linear APT-symmetric systems exhibit structural similarities with nonlinear dissipative systems, such as mutually…

Optics · Physics 2025-09-03 Takahiro Uemura , Kenta Takata , Masaya Notomi

Viewing a quantum thermal machine as a non-Hermitian quantum system, we characterize in full generality its analytical time-dependent dynamics by deriving the spectrum of its non-Hermitian Liouvillian for an arbitrary initial state. We show…

Quantum Physics · Physics 2021-12-14 Shishir Khandelwal , Nicolas Brunner , Géraldine Haack

Non-Hermitian systems have been at the center of intense research for over a decade, partly due to their nontrivial energy topology formed by intersecting Riemann manifolds with branch points known as exceptional points (EPs). This spectral…

Non-Hermitian physics has unlocked a wealth of unconventional wave phenomena beyond the reach of Hermitian systems, with exceptional points (EPs) driving enhanced sensitivity, nonreciprocal transport, and topological behavior unique to…

A numerical algorithm is proposed to deal with parametric eigenvalue problems involving non-Hermitian matrices and is exploited to find location of defective eigenvalues in the parameter space of non-Hermitian parametric eigenvalue…

Computational Physics · Physics 2026-01-23 Benoit Nennig , Martin Ghienne , Emmanuel Perrey-Debain

Exceptional points are universal level degeneracies induced by non-Hermiticity. Whereas past decades witnessed their new physics, the unified understanding has yet to be obtained. Here we present the complete classification of generic…

Mesoscale and Nanoscale Physics · Physics 2019-08-13 Kohei Kawabata , Takumi Bessho , Masatoshi Sato

We investigate the existence of higher order exceptional points (EPs) in non-Hermitian systems, and show that $\mu$-fold EPs are stable in $\mu-1$ dimensions in the presence of anti-unitary symmetries that are local in parameter space, such…

Mesoscale and Nanoscale Physics · Physics 2021-10-27 Pierre Delplace , Tsuneya Yoshida , Yasuhiro Hatsugai

Non-Hermitian Hamiltonians describing open systems can feature singularities called exceptional points (EPs). Resonant frequencies become strongly dependent on externally applied perturbations near an EP which has given rise to the concept…

Instrumentation and Detectors · Physics 2020-04-02 Heming Wang , Yu-Hung Lai , Zhiquan Yuan , Myoung-Gyun Suh , Kerry Vahala

Exceptional bound (EB) states represent an unique new class of robust bound states protected by the defectiveness of non-Hermitian exceptional points. Conceptually distinct from the more well-known topological states and non-Hermitian skin…

Quantum Physics · Physics 2024-07-02 Deyuan Zou , Tian Chen , Haiyu Meng , Yee Sin Ang , Xiangdong Zhang , Ching Hua Lee