Ground state cooling of micromechanical oscillators in the unresolved sideband regime induced by a quantum well
We theoretically demonstrate the ground state cooling of a mechanical oscillator in an optomechanical cavity in the presence of a quantum well, in the unresolved sideband regime. Due to the presence of the quantum well, the cavity response gets modified and leads to asymmetric heating and cooling processes. The cooling rate of the mechanical resonator can potentially be enhanced by tuning the cavity field detuning. It is demonstrated that, even when the cavity is in the unresolved sideband regime, the effective interaction of the exciton and mechanical modes can bring the system back to an effective resolved sideband regime. The time evolution of the mean phonon number in the mechanical resonator is studied using the quantum master equation. The average phonon occupancy in the mechanical resonator tends to 0 with time, exhibiting dynamic controllability of cavity dissipation.