Stimulated Raman scattering spectrum narrowing under picosecond pulse train pumping

A multiple narrowing of the stimulated Raman scattering (SRS) spectrum in water has been observed (350-400 cm-1to 100 cm-1) when pumped by 64-ps laser pulses train (λ=540 nm). Additionally, laser pulses temporal broadening has been detected when exciting SRS in water. Duration of the Stokes component pulses in the incident direction has been measured and amounted to ~77 ps.