Tunable Second-Order Sideband Generation in a Hybrid Cavity-Atom Optomechanical System

Second-order sideband generation in a hybrid cavity-atom optomechanical system is studied analytically and the modulation effect of trapped atoms on the spectrum of the second-order sideband generation is discussed. We find that second-order sideband generation exhibits a completely different varying trend versus the atomic coupling strength. Three different regimes are identified depending on the detuning between the atomic mode and the optical mode. In the resonance regime, second-order sideband generation is suppressed due to the decrease of cavity field. In the near resonance regime, second-order sideband generation can be significantly enhanced due to the amplification of the mechanical oscillation. In the off-resonance regime, the system can reduce to the conventional optomechanical system and there is no obvious change in the spectrum of the second-order sideband generation as the atomic coupling strength changes. These results lead to good tunability of second-order sideband generation and may find applications in manipulation of light propagation.