NONLINEAR OPTICAL DEVICE AND METHOD FOR MANUFACTURING THE SAME AS WELL AS OPTICAL CONVERSION DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain high wavelength conversion efficiency, to allow propagation of both of TE and TM polarized waves and to prevent the conversion efficiency from depending upon the polarized waves. SOLUTION: LiNbxTa1-xO3 (0<=x<=1) which is periodically inverted in part of spontaneous polarization is used as a nonlinear optical medium, LiNbO3 is used for a core part for guiding light into this medium and LiNbxTa1-xO3 is used for a clad part adjacent to this core part. Substantially only the core part is subjected to a proton exchange.