Asymmetric spectral broadening of sub-picosecond laser pulse in BaWO crystal: interplay of self-phase modulation, stimulated Raman scattering, and orientational Kerr nonlinearity.

Spectral broadening of 0.3 ps 515 nm laser pulse in a highly Raman-active crystal and fused silica demonstrates significantly different behavior with the incident pulse energy. While the broadening in fused silica is fairly symmetric with respect to the pump laser pulse wavelength, the Stokes wing broadening in the crystal is 2 times wider than that of anti-Stokes wing, the former demonstrating a step-like increase with the pulse energy.