Theoretical Considerations on Millimeter Wave Generation by Optical Frequency Mixing

The generation of radiation by miing optical maser signals is one possible method for closing the gap between microwaves and infrared. The conversion efficiency attainable with different types of nonlinear media is considered. It is shown that lossless nonlinear media, such as dielectrics, have very low conversion efficiency properties, regardless of the way they are used. Nonlinear resistive media, on the other hand, have efficiencies up to 25 per cent, independently of the frequency conversion ratio. Consequently, in order to generate wavelengths in the nillimeter range by mixing optical maser outputs, the materials used should involve nonlinear dissipative processes.