Observation of Laser-Induced Parallel Ridges in Y-cut Lithium Niobate Crystals

G. Assanto and F. Ricciardiello

J. Mat. Sci. Lett. 8, 971-973 (1989)


The characteristics of prism coupling of finite-width beams into nonlinear waveguides composed of media with diffusive nonlinearities (thermal, etc.) are calculated by including a one dimensional diffusion equation for the nonlocal nonlinearity. The resulting longitudinal feedback leads to bistability, and the threshold value for the minimum diffusion length varies inversely with the angular detuning.