Magnon-squeezing-enhanced slow light and second-order sideband in cavity magnomechanics

Cavity magnomechanics (CMM) has rapidly become a new research field of cavity quantum electrodynamics for studying quantum information processing and sensing. Here, we theoretically study the magnomechanically induced transparency effect in a cavity magnomechanical system, focusing on the role of magnon squeezing in enhancing and controlling the group delay of the transmitted light. As a result, we find that the magnon number can be strongly affected by magnon squeezing, accompanied by a steerable transmission rate and controllable fast-to-slow light switching. In particular, in the photon-magnon strong-coupling scenario, the group delay of the probe field can be enhanced by about three times by using magnon squeezing compared to the case without magnon squeezing. Moreover, due to the presence of magnon squeezing, the efficiency of the second-order sideband in the photon-magnon weak-coupling scenario can also be enhanced compared to the case without magnon squeezing. These results provide tools to engineer CMM devices with magnon squeezing for, e.g., light propagation and storage, and precision measurements of weak signals.