Low threshold quantum correlations via synthetic magnetism in Brillouin optomechanical system

We propose a scheme to generate low driving threshold quantum correlations in Brillouin optomechanical system based on synthetic magnetism. Our proposal consists of a mechanical (acoustic) resonator coupled to two optical modes through the standard optomechanical radiation pressure (an electrostrictive force). The electrostrictive force that couples the acoustic mode to the optical ones striggers Backward Stimulated Brillouin Scattering (BSBS) process in the system. Moreover, the mechanical and acoustic resonators are mechanically coupled through the coupling rate J_m, which is θ-phase modulated. Without a mechanical coupling, the generated quantum correlations, i.e., between optical and mechanical modes, require strong optomechanical and acoustic couplings. By accounting phonon hopping coupling, the synthetic magnetism is induced and the quantum correlations are generated for low coupling strengths. The generated quantum correlations display sudden death and revival phenomena, and are robust against thermal noise. Our results suggest a way for low threshold quantum correlations generation, and are useful for quantum communications, quantum sensors, and quantum computational tasks.