Optimizing second harmonic generation in a circular cylindrical waveguide with embedded periodically arranged tubelets of nonlinear susceptibility

摘要

Optical second-harmonic generation (SHG) is studied for the confined geometryof a circular cylindrical waveguide or optical fiber. A model situation of highsymmetry is considered where the material with nonlinear susceptibility isisotropic and distributed in radially symmetric manner about the axis. Inaddition it is assumed that the material of high second-order nonlinearityconsists of a thin circular layer, with periodic variation in the axialdirection - similar to a usual quasi-phasematched configuration. One canoptimize the efficiency of SHG by choosing the period of the array such that aBragg condition is satisfied. Depletion is studied in the framework ofmode-coupling theory. ?