SrCdSnQ₄ (Q = S and Se): infrared nonlinear optical chalcogenides with mixed NLO-active and synergetic distorted motifs

Abstract

Two new infrared (IR) nonlinear optical (NLO) chalcogenides, SrCdSnQ4 (Q = S and Se) (1 and 2), were obtained by mixing NLO-active metal chalcogenides and d10 metal tetrahedral motifs in an alkali metal-containing system.

BaHgGeSe4 and SrHgGeSe4: Two New Hg-Based Infrared Nonlinear Optical Materials

“…BaHgGeSe 4 and SrHgGeSe 4 are outstanding as IR NLO materials because they exhibit strong SHG responses (∼5 × AgGaS 2 over particle sizes of 150–200 μm for 2090 nm fundamental light) and are phase-matchable (Figure c,d). Some other related Zn- and Cd-containing AM′MQ 4 compounds are also SHG-active, but they show weak or modest SHG responses (BaZnSiSe 4 , 0.3 × AgGaS 2 ; BaZnGeSe 4 , 1 × AgGaS 2 ; SrCdGeS 4 , 2 × AgGaS 2 ), are non-phase-matchable (BaCdSnS 4 , 5 × AgGaS 2 ; BaCdSnSe 4 , 2 × AgGaS 2 ), or possess a smaller band gap (1.94 eV for SrCdGeSe 4 ), making them less competitive for practical application. ,,− The differences in SHG responses can be understood in terms of structure and bonding. The NLO behavior originates from the cooperative arrangement of the SHG-active structural units, namely, the M′Se 4 and MSe 4 tetrahedra.…”

Structural modification from centrosymmetric Rb4Hg2Ge2S8 to noncentrosymmetric (Na3Rb)Hg2Ge2S8: mixed alkali metals strategy for infrared nonlinear optical material design

“…17 Under the guidance of these ideas, high-performance IR NLO materials with tetrahedron [MQ 4 ] n − as the NLO functional motif have been extensively studied, such as BaGa 4 Q 7 (Q = S, Se), 18,19 BaGa 2 MQ 6 (M = Si, Ge; Q = S, Se), 20 M II 3 P 2 S 8 (M II = Zn, Hg), 21,22 and AM II M IV Q 4 (A = Eu, Sr, Ba; M II = Mn, Zn, Cd, Hg; M IV = Si, Ge, Sn; Q = S, Se). 23–28 A common strategy for broadening band gaps is introducing alkali or alkaline earth metals to these compounds. However, the interaction between alkali or alkaline earth metal cations and anions ( i.e.…”

Infrared nonlinear optical sulfide CsCd4In5S12 exhibiting large second harmonic generation response

“…Infrared nonlinear optical (IR-NLO) crystals, as crucial materials for laser frequency conversion, have attracted extensive attention due to their wide application in civilian and military fields such as optical information processing, laser guidance and molecular spectroscopy. [1][2][3][4][5][6][7][8][9] Currently, the commercial IR-NLO materials AgGaS 2 10 (AGS) and AgGaSe 2 11 (AGSe) unfortunately suffer from their own drawbacks such as a low LIDT, phase mismatch and two-photon absorption (TPA). [12][13][14][15][16][17][18] The development of new high performance IR-NLO materials is very significant; however, many challenges remain.…”

“…[27][28][29][30][31][32][33] Combining various NLO-active FBUs into one structure with consistent orientation is an effective strategy for the construction of new NLO materials with balanced performances. For example, diamond-like super-tetrahedra constructed using multiple aligned tetrahedra have been demonstrated as excellent materials for IR-NLO chalcogenides such as Ba 5 CdGa 6 Se 15 , 27 SrCdSnQ 4 (Q = S, Se) 8 and AZn 4 In 5 Se 12 (A = Rb + , Cs + ). 34 Meanwhile, enhancing the distortion degree of FBUs and diversifying asymmetric FBUs can effectively improve the formation possibility of NCS structures with large SHG response, which is observed in KHg 4 Ga 5 Se 12 disordered by Hg and Ga with a large SHG effect.…”