Influence of absorption on stability of terahertz difference frequency generation

摘要

This work presents numerical studies of the stability feature of terahertz difference frequency generation (THz-DFG) with a ZnGeP2 crystal using two pump wavelengths. We found that the maximum output of a THz wave is located in the unstable output region because of the competitive equilibrium between the absorption and the gain. Furthermore, the output stability is dependent on the pump stability. Different from the results at the pump wavelength of 9.588 mu m, there is neither an appropriate stable output region nor gain saturation region at the pump wavelength of 1.064 mu m for a larger absorption coefficient. This work demonstrates that the stable output region of the THz wave is difficult to obtain when the pump absorption is excessively large in DFG. (C) 2016 Optical Society of America