Abstract
Exceptional bound(EB)states represent a 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 states,they were recently discovered as a novel source of neg-ative entanglement entropy in the quantum entanglement context.Yet,EB states have been physically elusive,being originally interpreted as negative probability eigenstates of the propagator of non-Hermitian Fermi gases.In this work,we show that EB states are in fact far more ubiquitous,also arising robustly in broad classes of systems whether classical or quantum.This hinges crucially on a newly-discovered spectral flow that rigorously justifies the EB nature of small candidate lattice systems.As a highlight,we present their first experimental realization through an electrical circuit,where they man-ifest as prominent stable resonant voltage profiles.Our work brings a hitherto elusive but fundamentally distinctive quantum phenomenon into the realm of classical metamaterials,and provides a novel path-way for the engineering of robust modes in otherwise sensitive systems.
基金项目
National Key R&D Program of China(2022YFA1404904)
National Research Foundation Singapore grant under its QEP2.0 programme(NRF2021-QEP2-02-P09)
Ministry of Education(MOE)Tier-Ⅱ grant(MOE-T2EP50222-0008)
SUTD-ZJU Thematic Research(SUTD-ZJUTR202203)
NETL
NSTL
万方数据