Femtosecond transient grating studies in CS2

We explore transient grating formation in CS
2
with femtosecond pulses. The spatially periodic excitation changes the nonlinear refractive index of the medium periodically, resulting in diffraction of the probe beam. The pump power dependence of the self-diffraction efficiency shows a second order power-law indicating the process involving a third-order nonlinearity. Time-resolved diffraction of the probe beam measured with a photodiode gives the third-order autocorrelated signal. CS
2
having large third order nonlinearity in a broad range of wavelengths in the visible and near-infrared, is proposed to be a promising candidate for measuring the pulse-widths for pulses generated from optical parametric amplifiers (OPA) using this technique.