Patent ID: 7436586

Claim:
A wavelength conversion system, comprising: a Mach-Zehnder interferometer including two optical waveguides; a non-linear medium provided on only one of the two optical waveguides, in which a third-order non-linear phenomenon occurs such that wavelength conversion is performed using four wave mixing; and a branching ratio adjustment section configured to adjust the branching ratio of multiplexed light produced by multiplexing signal light and pumping light so that the powers of the signal light and the pumping light which are to be emitted from the two optical waveguides are equal to each other; wherein said wavelength conversion system is configured such that the multiplexed light whose branching ratio is adjusted by said branching ratio adjustment section is introduced into the two optical waveguides, said non-linear medium generates phase conjugation light of the signal light by the third-order non-linear phenomenon and the light guided through the one optical waveguide and the light guided through the other one of the two optical waveguides interfere with each other so that the phase conjugation light is extracted as wavelength conversion light.