Three‐in‐One Strategy Constructing the First High‐Performance Nonlinear Optical Sulfide Crystallizing with the P4₃ Space Group

Abstract

The balance between large nonlinear optical (NLO) effect and wide bandgap is the key scientific issue for the exploration of infrared NLO materials. Targeting this issue, two new pentanary chalcogenides KGaGe1.37Sn0.63S6 (1) and KGaGe1.37Sn0.63Se6 (2) are obtained by the three‐in‐one strategy, viz. three types of fourfold‐coordinated metal elements co‐occupying the same site. They crystallize in the tetragonal P43 (1) and monoclinic Cc (2) space group. Their structures can be evolved from benchmark AgGaS2 (AGS) by suitable substitution. Remarkably, 1 is the first NLO sulfide crystallizing with the P43 space group, representing a new structure‐type NLO material. The structural relationship between 1 and 2 and the evolution from 1, 2 to AGS are also analyzed. Both 1 and 2 show balanced NLO properties. Specifically, 1 exhibits phase‐matchable SHG response of 0.6 × AGS, a wide bandgap of 3.50 eV, and a high laser damage threshold of 6.24 × AGS. Theoretical calculation results suggest that the Ga/Ge/Sn element ratios of the co‐occupied sites of 1 and 2 are the most appropriate for stabilizing the structures. The strategy adopted here will provide some inspiration for exploring new high‐performance NLO materials.

KHg4Ga3S9: A Hg-Based Sulfide with Nonlinear-Optical Activity in the A–MII–MIII–Q (A = Alkali Metal; MII = d10 Metal; MIII = Ga, In; Q = S, Se) System

“…Recently, sulfides have garnered great attention as IR NLO materials due to their large NLO coefficients and wide IR transparent regions. Combining diverse NLO fundamental motifs like different MQ 4 (M = Si, Ge, Sn, Ga, In; Q = S, Se) tetrahedra is regarded as a favorable routine to obtain potential IR NLO crystals, which can be supported by the cases of Li 2 Ga 2 GeS 6 ( E g = 3.62 eV; d ij = 1.2 × AGS), KGaGe 1.37 Sn 0.63 S 6 ( E g = 3.50 eV; d ij = 0.6 × AGS), CsGaSn 2 Se 6 ( E g = 1.87 eV; d ij = 3.5 × AGS), Ba 2 Ga 8 GeS 16 ( E g = 3.0 eV; d ij = 0.9 × AGS), and SnGa 2 GeSe 6 ( E g = 1.98 eV; d ij = 1.7 × AGS) . Alkali (A) metals are conducive to large band gaps for the avoidance of d–d/f–f electron transitions, which can further increase the LIDTs.…”

A new infrared nonlinear optical material BaZnGeS4 with a wide band gap and large nonlinear optical response

“…57 As shown in Fig. 3c, the experimental results indicate that BaZnGeS 4 achieves a good balance between a wide band gap (E g ≥ 3.0 eV) and large SHG response (≥0.5× AGS) for an anti-laser damage IR NLO material, 22,[66][67][68] which are comparable with those of typical alkali-and/or AEM-containing sulfide IR NLO materials developed recently, such as LiGaS 2 , 69 α-Li 2 ZnGeS 4 , 70 Li 4 MgGe 2 S 7 , 52 SrZnGeS 4 , 34 and SrCdSiS 4 71 (Fig. 3d).…”

Three-in-One Tetrahedral Functional Units Constructing Diamondlike Ag2In2SiS3.06Se2.94 with High-Performance Nonlinear-Optical Activity

“…Among them, KGaGe 1. 37 Se 0.63 S 6 37 is the first NLO sulfide crystallizing with the P4 3 space group. In order to explore potential metalchalcogenide IR NLO materials, an extensive survey has been performed, and the A 2 M III 2 M IV Q 6 (A = alkali or coin metal; M III = Ga, In; M IV = Si, Ge, Sn; Q = S, Se) family of compounds and related ones have attracted our attention in recent years.…”

“…We have made rich meaningful explorations for NLO-active metal chalcogenides. For example, KInSi 1.32 Sn 0.68 Se 6 , KGaGe 1.37 Se 0.63 Q 6 (Q = S, Se), and CsM III M IV SnSe 6 (M III = Ga, In; M IV = Si, Ge) in the AM III M IV 2 Q 6 (A = alkali; M III = Ga, In; M IV = Si, Ge, Sn; Q = S, Se) family have been found to have excellent NLO properties. Among them, KGaGe 1.37 Se 0.63 S 6 37 is the first NLO sulfide crystallizing with the P 4 3 space group.…”

“…For example, KInSi 1.32 Sn 0.68 Se 6 , 36 KGa-Ge 1. 37 Se 0.63 Q 6 (Q = S, Se), 37 and CsM III M IV SnSe 6 (M III = Ga, In; M IV = Si, Ge) 38 in the AM III M IV 2 Q 6 (A = alkali; M III = Ga, In; M IV = Si, Ge, Sn; Q = S, Se) family have been found to have excellent NLO properties. Among them, KGaGe 1.…”