SrZnGeS₄: A Dual‐Waveband Nonlinear Optical Material with a Transparency Spanning UV/Vis and Far‐IR Spectral Regions

Abstract

Non-linear optical chalcogenides with a wide band gap (E g ) and excellent NLO properties are key materials for highly desirable multiwaveband tunable optical parametric oscillators (OPOs). We exploit the "electronic structure engineer bucket effect" to develop a novel dual-waveband SrZnGeS 4 with an ultrawide transparency window. It exhibits an asymmetric Fdd2 structure that consists of layers formed by cornersharing [ZnGeS 6 ] dimers. SrZnGeS 4 is transparent from 0.30 to 23.6 μm, spanning the UV-, vis-, mid-and far-IR spectral regions and has the widest E g (3.63 eV) in the AeM II M IV Q 4 family to date. It exhibits phase matching, high SHG intensities (e.g., 11.0 × KDP and 17.5 × AGS under λ inc = 1450 and 950 nm, respectively), and a very high laser-induced damage threshold (35 × AGS). These results not only suggest bright prospects for high-power laser applications but may also enable applications of the multiwaveband OPO system from the UV-visible to far-IR regions.

The first polyanion-substitution-driven centrosymmetric-to-noncentrosymmetric structural transformation realizing an excellent nonlinear optical supramolecule [Cd4P2][CdBr4]

“…Owing to their frequency conversion capabilities, NLO crystalline materials have an irreplaceable role in solid-state laser efficiently generating coherent beams. 21–27 As potential IR NLO candidates, supramolecular pnictide halides constructed from host and guest lattice frameworks have the unique characteristics of adjustable functional motifs for structural diversity and flexible properties. 28 Therefore, exploring an expected NCS pnictide halide as an ideal IR NLO material is urgently needed.…”