Optical Waveguides in Organic Crystals of Polycyclic Arenes

Abstract Organic crystals which can confine and guide optical waves on command are currently of considerable interest because of their tremendous potentials in broadband communications, optoelectronic devices, high‐capacity information storage, etc. Polycyclic arenes, with tunable molecular structures, packing modes, and photophysical properties, are a highly versatile class of organic materials, applicable as optical waveguide crystals. In this review, the optical waveguides of polycyclic arene‐based crystals are discussed, focusing on the molecular design, packing structures, crystal engineering, and the corresponding photonic properties. Moreover, several proof‐of‐concept devices are also shown. This review summarizes the current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of optical waveguiding materials.