Photo‐Reconfigurable Supercoupling Induced Transparency in On‐Chip Topological Edge State Cavities

Abstract

ABSTRACT Electromagnetically induced transparency is a quantum interference effect that eliminates optical absorption in an opaque medium. The resulting narrow transparency window, accompanied by a pronounced slow‐light effect, has enabled extensive applications in light storage, quantum information processing, and nonlinear optics. Recently, topological photonic systems have emerged as a powerful platform for robust on‐chip light manipulation with topological protection. Here, we demonstrate a form of induced transparency enabled by the supercoupling between a leaky and a guided topological edge state cavity (TESC). The local valley vortices facilitate coupling between TESCs even across a distance of 4.3 wavelengths and induce a transparency window with negligible reflection due to the valley‐locked momentum. When the supercoupled TESCs system operates in the strong‐driving regime, frequency detuning of TESCs leads to strong mode splitting and a clear avoided crossing. Using an optical pump to photoexcite the all‐silicon TESCs in the weak‐driving regime, we achieve photo‐reconfigurable supercoupling induced transparency (SIT), allowing dynamic control of group delay while maintaining constant transmittance. SIT opens new possibilities for manipulating light flow and controlling slow‐light effects, offering promising applications in on‐chip optical and quantum information processing.