Quantum oscillator in a Kerr-nonlinear blackbody

In the present paper, a charged oscillator in a harmonic potential well interacting with a Kerr-nonlinear blackbody is investigated. A quantum Langevin equation is derived. It is shown that below a transition temperature T-c, the memory function is a decreasing function of the Kerr-nonlinear coefficient. In the large-cutoff limit, the free-energy shift is a complicated function of temperature which is no longer a simply T-2-dependent function. The energy level shift of an oscillator in a normal blackbody is negative, while in our Kerr-nonlinear blackbody, only near zero temperature is the corresponding energy level shift negative. As the temperature increases to the transition temperature T-c, the corresponding energy level shift becomes a large positive value. Above T-c, our results are the same as those found in a normal blackbody.