Deep ultraviolet transparent borophosphates LiAB2P2O9 (A = NH4, K) and LiNaB2P2O8(OH)2·H2O exhibiting a moderate second-harmonic generation response

There is still a high demand for new deep ultraviolet (deep-UV) nonlinear optical (NLO) materials, but synthesizing an ideal deep-UV NLO crystal remains a significant challenge. In this work, three...