Observation of loss-induced topological bound states in the continuum
Phys. Rev. B 113, 085405 – Published 3 February, 2026
DOI: https://doi.org/10.1103/ygsq-12q9
Abstract
Intrinsic loss is typically regarded as a detrimental factor that impairs system performance, especially in systems with bound states in the continuum (BICs). Here, we propose and experimentally realize another type of loss-induced BICs (LBICs) in a non-Hermitian system consisting of a one-dimensional two-coupled-resonators chain. By engineering dissipative coupling introduced by loss, we highlight the role of loss and realize a topological phase transition of the energy band from discrete energy levels to a continuous spectrum, which results in the topological edge states being embedded into the continuous spectrum, thus forming a LBIC. Such topological LBIC, which inherits the robustness of topological edge states, is observed experimentally in a circuit system. Our work provides a physics mechanism to design topological BIC and establishes a bridge between intrinsic loss and radiation channels in non-Hermitian systems.
