  Cooling of mesoscopic mechanical resonators represents a primary concern in
cavity optomechanics. Here in the strong optomechanical coupling regime, we
propose to dynamically control the cavity dissipation, which is able to
significantly accelerate the cooling process while strongly suppressing the
heating noise. Furthermore, the dynamic control is capable of overcoming
quantum backaction and reducing the cooling limit by several orders of
magnitude. The dynamic dissipation control provides new insights for tailoring
the optomechanical interaction and offers the prospect of exploring macroscopic
quantum physics.
