Stimulated Raman scattering in natural crystals of SrSO4, BaSO4 and PbSO4: High-order Stokes and anti-Stokes generation with single-wavelength UV, visible, and near-IR excitation, as well as cascaded up-conversion nonlinear χ (3) ⇆ χ (3) lasing effects under dual-wavelength picosecond collinear coherent pumping

Orthorhombic crystals of SrSO4, BaSO4, and PbSO4, known as natural crystals celestine, barite, and anglesite, were found to be attractive chi ((3))-active nonlinear optical materials. High-order Stokes and anti-Stokes picosecond generation that spans almost two octaves has been recorded with single-wavelength laser excitation in the UV, visible, and near-IR ranges. All recorded Raman induced lasing components were identified and attributed to the SRS-promoting vibration modes of the studied crystals (omega (SRS)a parts per thousand 999 cm(-1) for SrSO4,omega (SRS)a parts per thousand 985 cm(-1) for BaSO4 and omega (SRS)a parts per thousand 977 cm(-1) for PbSO4). Under dual-wavelength (lambda (f1)=1.06415 mu m + lambda (f2)=0.53207 mu m) collinear coherent picosecond pumping several new manifestations of cascaded chi ((3)) <-> chi ((3)) nonlinear up-conversion lasing effects were observed in BaSO4 and SrSO4 crystals. We classify all three studied sulfate crystals as promising SRS-active materials for Raman laser frequency converters and as efficient chi ((3))-crystals that efficiently generate Stokes and anti-Stokes frequency combs, which can enable experiments of ultra-short pulse syntheses.