  A cavity optomechanical system is initiated by a radiation pressure of a
cavity field onto a mirror element acting as a quantum resonator. This
radiation pressure can control the thermodynamic character of the mirror to
some extent, such as cooling its effective temperature. Here we show that by
properly engineering the spectral density of a thermal heat bath that interacts
with a quantum system, the evolution of the quantum system can be effectively
turned on and off. Inside a cavity optomechanical system, when the heat bath is
realized by a multi-mode oscillator modeling of the mirror, this on-off effect
translates to infusion or extraction of heat energy in and out of the cavity
field, facilitating a four-stroke thermodynamic cycle.
