Analytical Study of Nonclassical Behaviour for a Disturbed Non-Degenerated Parameter Amplifier

We analytically discuss the nonclassical behaviour for a disturbed non-degenerated parameter amplifier. The thermal Glauber--Sudarshan diagonal presentation (GSP) function for the system is derived. The detailed analysis on the threshold temperatures of both the individual photon subsystem and the complete photon--photon complex is presented. The effect of the photon--photon interaction on the threshold temperature is observed.