Emergent Deep‐Ultraviolet Nonlinear Optical Candidates

Abstract

Advances in the generation of coherent lasers below 200 nm and its driven equipment and technologies have greatly spurred the development of nonlinear optical (NLO) materials with the capability to phase‐matching in the deep‐ultraviolet (deep‐UV) spectral regions. However, few crystals can meet the technical demands and studies to date have focused mainly on finding the next competitive candidates. Consequently, several crystals have emerged that hold great potential for the production of deep‐UV harmonic coherent light, which benefit from the newly developed system with novel NLO‐active units and chromophores. Herein, the authors provide a comprehensive review of the developments of emergent candidates in the field of deep‐UV NLO materials, discussing the recent efforts and active advances in searching of superior systems and in understanding of its structure‐property relationships. We aim to provide a clear perspective on the current emergent deep‐UV NLO candidates, and to accelerate the finding of next candidates with high performances to meet the urgent demands.