Polarization insensitive wavelength conversions by a LiNbO3 waveguide using a multi-ring configuration

A novel configuration is proposed for polarization insensitive wavelength conversions using a LiNbO3 waveguide with a periodically domain inverted structure. The proposed configuration consists of multiple rings, which are connected by a polarization sensitive wavelength converter such as the LiNbO3 waveguide described. One ring containing a pump light source is used to pump the wavelength converter bidirectionally, while the other rings containing a polarization beam splitter and a 90 degrees polarization rotator are used to couple in the input signal and extract the converted light. The proposed method is proven experimentally by the wavelength conversion based on sum frequency generation.