Reconfigurable Non‐Hermitian Topological Photonic Lattice via Reversible Quantum Dot Waveguides

Abstract

ABSTRACT Non‐Hermitian systems extend conventional Hermitian quantum frameworks by incorporating factors like gain and loss, giving rise to novel phenomena such as exceptional points and the non‐Hermitian skin effect. Building on these foundations, non‐Hermitian topological photonics merges them with topological band theory, enabling unprecedented control of light. The tunability of non‐Hermitian parameters allows for on‐demand reconfigurable topological devices within a fixed platform, thereby bridging the gap between exotic non‐Hermitian topological phenomena and practical applications. Here, we present a reconfigurable non‐Hermitian topological photonic lattice with tunable loss, realized on a novel platform of reversible perovskite quantum dot waveguide arrays. By strategically modulating the waveguide loss, we experimentally demonstrate a non‐Hermitian‐induced topological phase transition and the emergence of interface states. The reversible and tunable characteristics of perovskite quantum dot waveguides establish a versatile platform for exploring topological states and advancing on‐chip photonic applications.