Generating squeezing and enhancing entanglement in an opto-magnomechanical system via pump modulation

We propose schemes for generating quantum squeezing and enhancing entanglement in an opto-magnomechanical configuration by periodically modulating the driving field. The system consists of an optical cavity and a ferrimagnetic yttrium-iron-garnet micro-bridge supporting a magnon mode and a mechanical vibration mode, in which the mechanical mode couples to the optical mode and the magnon mode via radiation pressure and magnetostrictive interaction, respectively. The optical mode and the magnon mode are driven by classical fields, and the amplitude of the laser field driving the optical cavity is periodically modulated. We find that when the classical fields are red-detuned and their anti-Stokes sidebands scattered by the mechanical motion resonate with the corresponding driven modes, all the modes in the system will be squeezed simultaneously, and the mechanical squeezing can exceed the 3-dB limit. Furthermore, when the driving laser field is red-detuned and the microwave field is blue-detuned, both the bipartite and tripartite entanglements will be generated, and compared to the case without periodical modulation, the entanglements are significantly enhanced. We also show that the schemes have strong robustness against the system dissipations and environmental temperature. Our schemes may provide efficient quantum resources for quantum precision measurement and quantum information processing.