Abstract

Instabilities in the interaction of counterpropagating laser beams in a nonlinear medium can have important consequences for nonlinear optical processes such as optical bistability and phase conjugation. We have performed a theoretical study of the polarization characteristics of two counterpropagating waves in an isotropic Kerr medium in order to determine the stability of the multivalued solutions found by previous workers.¹ Our method involves numerical integration of the coupled-amplitude equations describing the spatial and temporal evolution of the counterpropagating vector waves.² Our results show that the multiply stable solutions for the output polarizations of the two vector fields show hysteresis, and that the order in which the two fields are turned on determines which solution is reached. For even higher input intensities we find that the output polarizations fluctuate in time.

© 1986 Optical Society of America