Optical Kerr effect induced by ultrashort laser pulses

A generalization of the classical molecular-optics theory of the optical Kerr effect (OKE) is presented which permits a study of the effect when induced by ultrashort laser pulses. Explicit relationships between results from this general theory and often-used phenomenological equations governing the temporal behavior of the OKE are established. Numerical results are presented for the liquids carbon disulfide and nitrobenzene, illustrating in detail the temporal nature and intensity of the birefringence induced in these liquids by ultrashort laser pulses. The importance of these results is discussed in connection with a number of self-induced nonlinear phenomena arising from the OKE as well as in conjunction with the OKE shutter switched by an ultrashort laser pulse. In addition, a discussion is given of the nature of the birefringence induced by picosecond laser pulses as well as aspects of the extension of OKE photography to the subpicosecond domain.