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arXiv · 2310.19111

Magnomechanically controlled Goos-H\"{a}nchen shift in cavity QED

Abstract

Phenomena involving interactions among magnons, phonons, and photons in cavity magnomechanical systems have attracted considerable attention recently, owing to their potential applications in the microwave frequency range. One such important effect is the response of a probe field to such tripartite interaction between photon-magnon-phonon. In this paper, we study Goos-H\"{a}nchen shift (GHS) of a reflected probe field in a cavity magnomechanical system. We consider a YIG sphere positioned within a microwave cavity. A microwave control field directly drives the magnon mode in YIG sphere, whereas the cavity is driven via a weak probe field. Our results show that the GHS can be coherently controlled through magnon-phonon coupling via the control field. For instance, GHS can be tuned from positive to negative by tuning the magnon-phonon coupling. Similarly, the effective cavity detuning is another important controlling parameter for GHS. Furthermore, we observe that the enhancement of GHS occurs when magnon-phonon coupling is weak at resonance, and when the magnon-photon coupling is approximately equal to the loss of microwave photons. Our findings may have potential significance in applications related to microwave switching and sensing.

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Muhammad Waseem, Muhammad Irfan, Shahid Qamar. 2023-10-29. Magnomechanically controlled Goos-H\"{a}nchen shift in cavity QED. https://doi.org/10.1103/physreva.110.033711

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