Flourishing Organic Active Optical Waveguides with Diversity and Creativity

Conventional dielectric waveguides are limited by their propagation mechanisms and relatively large dimensions. A promising alternative lies in replacing electronic devices with photonic ones. In contrast, organic crystals featuring a regular shape can create optical waveguides that confine photons to micro‐ and nanoscales. This paper offers a concise overview of the preparation methods for using organic crystals as optical waveguide media, along with an exploration of the optical waveguide phenomena within these 1D or 2D, monolayer or multi‐tiered microcrystals, demonstrating the broad application prospects of optical waveguides. It is concluded by summarizing the current challenges and future prospects in this field.