Pump polarization dependence of the optical Kerr gate with elliptically polarized probe light

Abstract

Based on the light-induced polarization ellipse rotation effect, we propose an optical Kerr gate (OKG) in which elliptically polarized probe light is used by introducing a pair of crossed quarter-wave plates into the conventional OKG arrangement, placed just before and after the Kerr medium. Transient birefringence induced by the pump beam in the Kerr medium leads to a rotation of the polarization ellipse of the probe beam, hence part of the probe beam would pass through the OKG. Theoretical calculations and experimental results both indicate that the OKG signal intensity would reach the optimum value independent of the pump polarization direction when the probe beam is circularly polarized. This modified OKG measurement is suitable to detect the third-order nonlinearities induced in anisotropic materials.