Abstract
We investigate the cooling of mechanical resonator in the quantum regime by using the effective master equations, which can be applicable with and without rotating-wave approximation (RWA) in linear regime. We show that the improved lower bound for the final occupancy of the mechanical resonator can be attained by inclusion of the anti-resonance terms in the resolved sideband (RSB) regime. We establish that the self squeezing cavity modes can enhance the cooling in optomechanical cavity.