Intracavity-Squeezed Optomechanical Cooling

Quantum ground-state cooling of macroscopic mechanical resonators is of essential importance to both fundamental physics and applied science. The conventional method of laser cooling is limited by the quantum backaction, which requires the mechanical sideband to be resolved in order to cool to ground state. Herein, an idea to break the quantum backaction limit by engineering intracavity optical squeezing is presented. It gives rise to quantum interference for all the dissipation channels, and under certain circumstances can totally remove the influence of the cavity dissipation and the resultant quantum backaction, with much lower cooling limit irrespective of the sideband resolution. It is shown that the scheme enables ground-state cooling in the highly unresolved sideband limit and it also works beyond the weak coupling regime, which provides the opportunity for quantum manipulation of macroscopic mechanical systems.