Nonlinear Optical Crystals with Planar Conjugated Configuration

Abstract

Abstract: Ultraviolet nonlinear optical (NLO) crystals are the key materials to realize the development of ultraviolet solid-state lasers. At present, NLO crystals mainly rely on borate crystals, but the existing NLO crystals could not meet the applications fully. While it is increasingly difficult to find new NLO crystals, so it is particularly urgent to develop new material systems. From the relationship between borate structures and optical and nonlinear optical properties, it can be known that borates which containing planar conjugated groups have the characteristics of large frequency doubling coefficient, suitable birefringence and short UV cut-off edge. Group with planar conjugated configuration is the core functional unit of borate NLO crystals. The study of expanding planar conjugated groups based on geometric configuration is an important idea for exploring new systems of UV nonlinear optical materials. Based on these, our team proposes to expand the exploration scope of UV NLO crystals by studying CO₃, NO₃, C(NH₂)₃ groups with planar triangular conjugated structures and HC₃N₃O₃, H₂C₄N₂O₃ groups with planar six-member ring conjuated structures. The research results obtained by our team in the exploration of UV crystals of carbonate, nitrate, guanidine, cyanurate and barbiturate in recent years are mainly introduced in this paper.

Key words: planar conjugated configuration, nonlinear optical crystal, carbonate, nitrate, guanidine, cyanurate, barbiturate

CLC Number:

O641

FAN Huixin, LUO Min, YE Ning. Nonlinear Optical Crystals with Planar Conjugated Configuration[J]. Journal of Synthetic Crystals, 2022, 51(9-10): 1588-1597.

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