Stimulated Raman scattering in disodium ditungstate crystal

Spontaneous and stimulated Raman scattering are studied in Na 2 W 2 O 7 crystal with an orthorhombic structure. The polarized Raman scattering spectra corresponding to all the six independent Raman tensor components are measured. The frequencies of the registered vibrational modes are identified. The most intense Raman mode is observed at 956.3 cm −1 with a linewidth of 3.5 cm −1 . The first observation of stimulated Raman scattering in Na 2 W 2 O 7 under excitation by the second harmonic of a mode-locked Nd:YLF laser with a pulse duration of 25 ps is reported. Raman gains at a wavelength of 523.5 nm in Na 2 W 2 O 7 and KGd(WO 4 ) 2 crystals are measured. We believe that disodium ditungstate crystal is a promising medium for Raman laser converters.