β-BaGa₄Se₇: a promising IR nonlinear optical crystal designed by predictable structural rearrangement

Abstract

Rationally designing new inorganic materials with specific functional properties is a fascinating challenge. This is particularly true with the nonlinear optical (NLO) crystals which can expand the spectral ranges of...

The Combination of Structure Prediction and Experiment for the Exploration of Alkali‐Earth Metal‐Contained Chalcopyrite‐Like IR Nonlinear Optical Material

“…[ 15,28,33,39 ] What's more, the refractive index difference (RID) of DCL‐MgGa 2 Se 4 was investigated by the polarizing microscope method. [ 4d,10,11,40 ] The optical path differences of the DCL‐MgGa 2 Se 4 crystal at 546 nm were 1.48 µm, and the thickness of the crystal was measured to be 31 µm (Figure S8, Supporting Information). According to the Equation () in the Experimental Section, the RID was calculated to be ≈0.048 at 546 nm, which is consistent with the PM behavior.…”

“…5 pol) with Berek compensator. [ 4d,10,11,40 ] The wavelength of the light source was 546 nm. The RID value is calculated by the following formula: $$\begin{equation} R=\left|{N}_{g}-{N}_{p}\right|\ensuremath{\times{}}T= \Delta n\ensuremath{\times{}}T \end{equation}$$in which R represents the optical path difference; N g , N p , and Δ n means the refractive index of fast light and slow light, the RID, respectively, and T denotes the thickness of the crystal.…”

“…[ 6 ] Among them, selenides normally exhibit wider IR transparent regions, larger SHG responses, and lower melting points, but smaller band gaps than sulfides. [ 7 ] Over the past decades, a plenty of selenides with good NLO properties like LiGaSe 2 , [ 8 ] α ‐BaGa 4 Se 7 , [ 9 ] β ‐BaGa 4 Se 7 , [ 10 ] β ‐BaGa 2 Se 4 , [ 11 ] Li 2 ZnMSe 4 (M = Ge, Sn), [ 12 ] Li 2 CdMSe 4 (M = Ge, Sn), [ 13 ] Li 2 In 2 MSe 6 (M = Si, Ge), [ 14 ] Na 4 MgM 2 Se 6 (M = Si, Ge), [ 15 ] BaGa 2 MSe 6 (M = Si, Ge), [ 16 ] γ ‐NaAsSe 2 , [ 17 ] Na 6 MSe 4 (M = Zn, Cd), [ 18 ] CsM 3 Se 6 (M = Ga/Sn, In/Sn), [ 19 ] and AgLiGa 2 Se 4 [ 20 ] have been designed and synthesized successfully. However, to enhance the LIDT, the band gaps in selenides are still highly expected to be further improved.…”

Na4Ga8S14: a Ga-enriched wide band gap ternary alkali-metal sulfide with unique [Ga12S42] 12-membered rings

“…Interestingly, for the tunnel-like Ga-S 3D frameworks, the shape of the tunnels shows abundant diversity. Different from the 6-membered ring tunnel-like 3D framework in BaGa 4 S 7 , BaGa 4 Se 7 and LiGaS 2 , 20,24,25,55 and the 12-membered ring rectangular tunnel-like 3D framework in LiBa 4 Ga 5 Se 12 , 49 the formed 12-membered ring-like tunnels in Na 4 Ga 8 S 14 are rarely reported.…”

“…[15][16][17] To enlarge the band gap and enhance the laser-induced damage threshold (LIDT) of chalcogenides, introduction of alkali-and/or alkaline earthmetals has been demonstrated as a feasible method. [18][19][20][21] Recently, a great number of alkali-and/or alkaline earthmetal chalcogenides with wide band gaps have been developed by high temperature solid-state reactions. 22,23 For example, in 2008 Ye et al reported the fabrication of IR NLO material BaGa 4 S 7 , 24 which exhibited a large band gap, high LIDT, wide optically transparent region, and suitable second-order susceptibility coefficients.…”