All-optical wavelength conversions in PPLN waveguide with continuous and pulsed pumping

Abstract

A theoretical model for description of the cSFG/DFG is developed in this paper. The factors influence the poled period of PPLN is studied and the result shows that the poled period decreases while the temperature increases, and the poled period also changes while we choose different signal wavelengths. In our simulation, a pulsed light is injected into a PPLN waveguide as the signal, and then the performances of the wavelength conversion structures with two continuous waves and two pulsed lights are compared in detail by numerical simulation. The output of these two situations are educed while depletion, walk-off and nonlinear effect are all considered. The walk-off effects of output and conversion efficiency are studied in both cases. The results demonstrate that there is an obvious walk-off between input signal and output in the pulse pumped case, and in the CW case the converted wave width is boarder than that of input signal due to pulse dispersion. Factors that influence the conversion efficiency are also analyzed including the power of the pump light, the length of the PPLN waveguide and the experiment structure.