Wavelength converter

摘要

A wavelength converter has a periodic structure, where a nonlinear optical coefficient is spatially modulated at a fundamental period LAMBDA 0 and the phase of the period LAMBDA 0 is modulated nearly continuously at a period LAMBDA ph > LAMBDA 0. A conversion efficiency is made maximum when a phase mismatch amount DELTA beta equals 2 pi / LAMBDA 0+/-2 pi i/ LAMBDA ph (i=0, 1, ..., n, where n is a positive integer), 2 pi / LAMBDA 0+/-2 pi (2i+1)/ LAMBDA ph (i=0, 1, ..., n), or 2 pi / LAMBDA 0+2 pi i/ LAMBDA f (i=m, m+1, ..., n, where m and n are positive or negative integers satisfying ¾m¾ NOTEQUAL ¾n¾), thereby providing a wavelength converter and wavelength converting apparatus that can be designed to be able to cope with a desired number of pump wavelengths, prevent the reduction in the conversion efficiency, and be configured easily using a practical size of a nonlinear optical material.