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N onlinear optical (NLO) crystals are of great importance in producing coherent ultraviolet−visible (UV−vis), deep-UV (DUV), or infrared (IR) light sources for civil and military applications by frequency-conversion technology. 1−23 Borates are widely applied as short-wave NLO materials because of their large bandgaps and high laser damage threshold that originate from strongly covalent B−O bonds in [BO 3 ] 3− and [BO 4 ] 5− anionic groups, such as β-BaB 2 O 4 , 1 LiB 3 O 5 , 2 KBe 2 BO 3 F 2 , 3 etc.; unfortunately, they cannot be used in the IR region because of absorption resulting from their B− O vibration modes which limits the infrared transmission. Meanwhile, chalcogenides, 6 owing to its wide optical transmission range and strong NLO response, are wildly researched for IR NLO materials. Recently, in view of the performance drawbacks (low laser damage threshold (LDT) and harmful two photon absorption) of commercial IR NLO materials, 24−26 it is urgent to explore new excellent IR NLO materials 27−33 with suitable balance between wide bandgap (E g ≥ 3.0 eV) and large second harmonic generation (SHG) effect (NLO coefficient d ij ≥ 0.5 × benchmark AgGaS 2 ). 34

3D supercritical resolved light-induced magnetic holography makes possible 1872 Tbit/in3 ultrahigh-density data recording.