English
Related papers

Related papers: Mobile Exceptional Points Generate Momentum-Space …

200 papers

Higher-order exceptional points (EPs) govern non-Hermitian system dynamics through their enriched and sharpened spectral topology, yet the intrinsic topological fragility hinders robust experimental realization. Here, we present a scalable…

We investigate the astonishing physical aspects of Exceptional Points (EPs) in a 1D planar few-mode optical waveguide. The waveguide hosts four quasi-guided modes. Here interactions between the selected pair of modes are modulated by a…

We study the interplay of two distinct non-Hermitian parameters: directional coupling and onsite gain-loss, together with topology, in coupled one-dimensional (1D) non-Hermitian Su-Schrieffer-Heeger (SSH) chains. The SSH model represents…

Mesoscale and Nanoscale Physics · Physics 2023-08-14 Sayan Jana , Lea Sirota

We investigate non-Hermitian degeneracies, also known as exceptional points, in continous elastic media, and their potential application to the detection of mass and stiffness perturbations. Degenerate states are induced by enforcing…

Applied Physics · Physics 2021-02-24 M. I. N. Rosa , M. Mazzotti , M. Ruzzene

Exceptional points (EPs), ubiquitous non-Hermitian degeneracies, are central features in band structures where non-Hermitian Fermi arcs connect EPs and eigenvalue knots encircle them. Under open boundary conditions (OBCs), non-Hermitian…

Other Condensed Matter · Physics 2026-01-06 Yuancheng Zhao , Jia-Xin Zhong , Jing Lin , Yun Jing , Kun Ding

Exceptional points~(EPs) appear as degeneracies in the spectrum of non-Hermitian matrices at which the eigenvectors coalesce. In general, an EP of order $n$ may find room to emerge if $2(n-1)$ real constraints are imposed. Our results show…

Quantum Physics · Physics 2022-07-29 Sharareh Sayyad , Flore K. Kunst

Exceptional points (EPs) has seen substantial advances in both experiment and theory. However, in quantum systems, higher-order exceptional points remain of great interest and possess numerous intriguing properties yet to be fully explored.…

Quantum Gases · Physics 2025-01-22 Yu-Jun Liu , Ka Kwan Pak , Peng Ren , Mengbo Guo , Entong Zhao , Chengdong He , Gyu-Boong Jo

Exceptional points (EPs) are singularities of energy levels in non-Hermitian systems. In this Letter, we demonstrate the surface of EPs on a magnon polariton platform composed of coupled magnons and microwave photons. Our experiments show…

Mesoscale and Nanoscale Physics · Physics 2019-12-11 Xufeng Zhang , Kun Ding , Dafei Jin , Xianjing Zhou , Jing Xu

Complex spectra of dissipative quantum systems may exhibit degeneracies known as exceptional points (EPs). At these points the systems' dynamics may undergo drastic changes. Phenomena associated with EPs and their applications have been…

Quantum Physics · Physics 2025-03-19 Andrei I. Pavlov , Yuval Gefen , Alexander Shnirman

Exceptional points (EPs) are singularities in the parameter space of a non-Hermitian system where eigenenergies and eigenstates coincide. They hold promise for enhancing sensing applications, but this is limited by the divergence of shot…

Optics · Physics 2025-04-07 Xu Zheng , Y. D. Chong

Eigenvalue problems for electromagnetic resonant states on open dielectric structures are non-Hermitian and may have exceptional points (EPs) at which two or more eigenfrequencies and the corresponding eigenfunctions coalesce. EPs of…

Optics · Physics 2020-04-07 Amgad Abdrabou , Ya Yan Lu

An astroid-shaped loop of exceptional points (EPs), comprising four cusps, is found to spawn from the triple degeneracy point in the Brillouin zone (BZ) of a Lieb lattice with nearest-neighbor hoppings when non-Hermiticity is introduced.…

Mesoscale and Nanoscale Physics · Physics 2021-01-01 Yi-Xin Xiao , Kun Ding , Ruo-Yang Zhang , Zhi Hong Hang , C. T. Chan

The concept of exceptional point (EP) is demonstrated experimentally in the case of a simple mechanical system consisting of two linearized coupled pendulums. Exceptional points correspond to specific values of the system parameters that…

Computational Physics · Physics 2024-02-08 Nicolas Even , Benoit Nennig , Gautier Lefebvre , Emmanuel Perrey-Debain

Parity-time (PT)-symmetric Hamiltonians have widespread significance in non-Hermitian physics. A PT-symmetric Hamiltonian can exhibit distinct phases with either real or complex eigenspectrum, while the transition points in between, the…

Quantum Physics · Physics 2021-07-13 Lei Xiao , Tianshu Deng , Kunkun Wang , Zhong Wang , Wei Yi , Peng Xue

Non-Hermitian spectral degeneracies, known as exceptional points (EPs), feature simultaneous coalescence of both eigenvalues and the associated eigenstates of a system. A host of intriguing EP effects and their applications have been…

Quantum Physics · Physics 2022-05-24 R. Huang , Ş. K. Özdemir , J. -Q. Liao , F. Minganti , L. -M. Kuang , Franco Nori , H. Jing

Exceptional points (EP) in non-Hermitian systems have been widely investigated due to their enhanced sensitivity in comparison to standard systems. In this letter, we report the observation of higher-order pseudo-Hermitian degeneracies in…

Applied Physics · Physics 2023-05-02 Ke Yin , Xianglin Hao , Yuangen Huang , Jianlong Zou , Xikui Ma , Tianyu Dong

One of the unique features of non-Hermitian~(NH) systems is the appearance of non-Hermitian degeneracies known as exceptional points~(EPs). The extensively studied defective EPs occur when the Hamiltonian becomes non-diagonalizable. Aside…

Quantum Physics · Physics 2023-12-11 Sharareh Sayyad , Marcus Stalhammar , Lukas Rodland , Flore K. Kunst

Eigenstate coalescence in non-Hermitian systems is widely observed in diverse scientific domains encompassing optics and open quantum systems. Recent investigations have revealed that adiabatic encircling of exceptional points (EPs) leads…

Quantum Physics · Physics 2023-06-13 Jung-Wan Ryu , Jae-Ho Han , Chang-Hwan Yi , Moon Jip Park , Hee Chul Park

Exceptional points (EPs), singularities in non-Hermitian systems where eigenvalues and eigenstates coalesce, exhibit a dramatically enhanced response to perturbations compared to Hermitian degeneracies. This makes them exceptional…

Quantum Physics · Physics 2025-11-24 Shu-Xuan Wang , Zhongbo Yan

Exceptional points (EPs) are degeneracies of classical and quantum open systems, which are studied in many areas of physics including optics, optoelectronics, plasmonics, and condensed matter physics. In the semiclassical regime, open…

‹ Prev 1 4 5 6 7 8 10 Next ›