Nonresonant Processes as a Basis for the Formation of New Relaxation Channels in the Theory of Quantum Optical Systems

The mechanisms for the pumping and decay of an "isolated" oscillator that can interact only nonresonantly with a neighboring oscillator of different frequency are presented. We show that if this neighboring oscillator is coupled to a broadband heat-bath field, the isolated oscillator begins to interact with this heat-bath field. A new relaxation channel attributable to the quantum interference of the interacting systems that is difficult or impossible to justify in terms of traditional approaches emerges as a result.