Transverse instabilities due to counterpropagation in Kerr media

Abstract

Counterpropagation of optical beams in Kerr media is shown to be unstable against transverse modulation. This is true for both focusing and defocusing media. Numerical studies show metastability, hysteresis, symmetry breaking, oscillations, and probable chaos. Transverse effects are likely to lower thresholds for known plane-wave counterpropagation instabilities. Similar effects can be expected in saturable media and lasers.