Tunable Second-Order Sideband Effects Based on Dual-Species BEC-Optomechanical Systems

We theoretically investigate a second-order optomechanically induced transparency process of a cigar-shaped dual-species Bose–Einstein condensate with nonlinear collisions trapped inside an optomechanical cavity. We find that atomic collisions provide linear couplings, which facilitate the mechanical mixing of the dual-species Bose–Einstein condensate. We derive analytical expressions of the output transmission intensity of the probe field and the dimensionless amplitude of the second-order sideband. The numerical results show that the transmission intensity and the dimensionless amplitude of the second-order sideband can be controlled by the control field intensities, the effective detuning, and the effective coupling strength of the Bogoliubov mode of the dual-species Bose–Einstein condensate and optical mode. Furthermore, the interspecies and intraspecies interactions are also used to control the transmission intensity and the dimensionless amplitude of the second-order sideband.