Calcium dithionate tetrahydrate, CaS₂O₆⋅4H₂O, a novel SRS-active crystal for octave-spanning many-phonon Stokes and anti-Stokes combs

Abstract

This paper introduces a novel SRS-active crystal, hexagonal CaS 2 O 6 •4H 2 O, which was found to be an attractive Raman gain material and a suitable subject for the study of numerous nonlinear lasing effects. Under picosecond laser pumping in the UV, visible and near-IR spectral region we observed various manifestations of Raman induced nonlinear interactions. All registered Stokes and anti-Stokes components are identified and attributed to the participating χ (3) -promoting phonon modes. In the appendix, we present new data on the SRS properties of another dithionate, Na 2 S 2 O 6 •2H 2 O.