Non-Hermitian degeneracies, also known as exceptional points (EPs), have been the focus of much attention due to their singular eigenvalue surface structure. Nevertheless, as pertaining to a non-Hermitian metasurface platform, the reduction of an eigenspace dimensionality at the EP has been ...
The spectral flow is determined by how the control loop encircles degeneracies, and this relationship is well understood for N=2 (where N is the number of oscillators in the system)4,5. Here we extend this description to arbitrary N. We show that control loops generically produce braids of ...
Non-Hermitian degeneracies,also known as exceptional points(EPs),have been the focus of much attention due to their singular eigenvalue surface structure.N... S Baek,HP Sang,D Oh,... - 光:科学与应用(英文版) 被引量: 0发表: 2023年 Experimental study of the high-order exceptional points ...
Observation of non-hermitian degeneracies in a chaotic exciton-polariton billiard. Nature 526, 554558 (2015). 7. Meng-Jun Hu, X.-M. H. & Zhang, Y.-S. Are observables necessarily Hermitian? Preprint at arXiv:1601.04287v1 (2015). 8. Moiseyev, N. Non-Hermitian Quantum Mechanics (...
The appearance and regions of existence of the edge modes are intimately related to exceptional points, i.e., degeneracies in the bulk spectra of the media. We find that the topological edge modes can be divided into three classes ("Hermitian-like", "non-Hermitian", and "mixed"), and ...
Leykam, D., Bliokh, K.Y., Huang, C., Chong, Y.D., Nori, F.: Edge modes, degeneracies, and topological numbers in non-hermitian systems. Phys. Rev. Lett. 118, 040401 (2017) Article ADS MathSciNet Google Scholar Xiong, Y.: Why does bulk boundary correspondence fail in some non-...
In non-Hermitian systems, defective band degeneracies called exceptional points can form exceptional lines (ELs) in 3D momentum space in the absence of any... RY Zhang,X Cui,WJ Chen,... - 《Communications Physics》 被引量: 0发表: 2022年 Degeneracy and defectiveness in non-Hermitian systems ...
Complex WKB analysis of energy-level degeneracies of non-Hermitian Hamiltonians The Hamiltonian H = p(2)+x(4)+iAx, where A is a real parameter, is investigated. The spectrum of H is discrete and entirely real and positive for \\A\\ < 3.169. As \\A\\ increases past this point, adja...
Exceptional points are degeneracies in the spectrum of non-Hermitian open systems where at least two eigen-frequencies and simultaneously the corresponding... J Kullig,D Grom,S Klembt,... - 光子学研究(英文) 被引量: 0发表: 2023年 Experimental realization of non-Abelian permutations in a three...
and these degeneracies are called nondefective degeneracy points. If only one ofκ+−(−+)(k) is zero,\({{{\mathcal{H}}}_{{{\rm{eff}}}({{{\bf{k}}})\)is nondiagonalizable, and the defective degeneracies whose eigenstates coalesce are known as exceptional points. Therefore, for...