Raman-induced signals in optical Kerr effect measurements of water with elliptically polarized pulses

In two-color optical Kerr effect measurements of water, additional signals can occur in the pulse overlap region if the energy difference between pump and probe pulses approaches the Raman resonance of the OH-stretch vibration. These features can be understood by taking into account the polarization of the pump beam and the chirp of the pulses. We present a simple model that describes well the experimental results and shows the dependence of these features on the ellipticity of the pump beam polarization.