Review of the development of nonlinear materials for mid-IR generation

Review and prospects of optical countermeasure technologies

“…The OCM applications do not call for special requirements for the optical components and materials. The conference proceedings include a couple of informative papers and reviews about dual-use bimorph mirrors [47], micro-structured optical fibres [48], non-linear optical materials [49], or infrared fibres [50].…”

Optical Parametric Amplification Techniques for the Generation of High-Energy Few-Optical-Cycles IR Pulses for Strong Field Applications

“…When the DFG process generates a seed pulse in the terahertz (THz) domain, the process is called optical rectification, and it is widely benefiting from a new generation of non-oxide materials capable of providing optical transparency up to tens of µm, among which AgGaSe 2 (AGSe), ZnGeP 2 (ZGP), GaSe, GaP and ZnTe. A full list of NLO materials is provided in [24] for applications in the near-IR and in [25][26][27] for applications in the mid-IR.…”

SnP2S6: A Promising Infrared Nonlinear Optical Crystal with Strong Nonresonant Second Harmonic Generation and Phase-Matchability

“…Currently, the commercially available infrared NLO crystals are AgGaS2, 8 AgGaSe2 9 and ZnGeP2. 9,10 They exhibit large NLO coefficients and broad transmission range; however, they also suffer some intrinsic drawbacks such as rather low laser induced damage threshold (LIDT) 11,12 and strong absorption of 1-2μm, 13 limiting the choice of pump lasers. 10,14 To qualify as a good NLO material, there are several criteria: (1) large SHG coefficients to have efficient NLO conversion;…”

“…(2) wide transparency window allowing broadband tunability; (3) large LIDT and (4) phasematchability for good SHG efficiency. 10,[15][16][17] It is well known that the main challenge in the discovery and optimization of NLO materials is the tradeoff between the bandgap and the magnitude of the NLO coefficients: materials with larger bandgaps typically have lower SHG coefficients but higher LIDTs. 17,18 Finding new infrared NLO crystals with a superior optimized set of optical properties to the current materials is a grand challenge in this field.…”

“…Traditional NLO materials such as β-BaB 2 O 4 , LiB 3 O 5 , and LiNbO 3 are of limited usage in the mid-infrared regime due to strong multiphonon absorption. Currently, the commercially available infrared NLO crystals are AgGaS 2 , AgGaSe 2 ,and ZnGeP 2 . , They exhibit large NLO coefficients and a broad transmission range; however, they also suffer some intrinsic drawbacks such as a rather low laser induced damage threshold (LIDT) , and strong absorption of 1-2 μm, limiting the choice of pump lasers. , To qualify as a good NLO material, there are several criteria: (1) large SHG coefficients to have efficient NLO conversion; (2) wide transparency window allowing broad-band tunability; (3) large LIDT, and (4) phase-matchability for good SHG efficiency. ,− It is well known that the main challenge in the discovery and optimization of NLO materials is the tradeoff between the bandgap and the magnitude of the NLO coefficients: materials with larger bandgaps typically have lower SHG coefficients but higher LIDTs. , Finding new infrared NLO crystals with a superior optimized set of optical properties to the current materials is a grand challenge in this field.…”