Transversely pumped nonlinear conversion structure which generates counterpropagating guided waves: Theory and numerical modeling

A transversely pumped, nonlinear conversion structure which generates count erpropagating, guided signal and idler beams is examined. Existing scalar t heory is extended to include the vector nature of the electromagnetic field s. Based on these results, a detailed simulation of proposed GaAs-AlGaAs st ructures is described. The results of the simulations highlight pitfalls no t obvious in the original work, The simulations indicate, however, that pro per design of the structure should provide a compact, highly efficient meth od of nonlinear optical conversion. In particular, a structure designed to convert light at 980 nm to light at 1.55 mum is predicted to have a thresho ld intensity of 4.9 MW/cm(2), which is comparable to thresholds observed in parametric oscillators which use periodically poled lithium niobate.