Enhanced Magnon Synchronization in Coupled WGM Optomagnonic Resonators with Phase-Dependent Photon Hopping

Abstract: We investigate quantum synchronization in a coupled cavity optomagnonic system which consists of two spatially separated optical whispering-gallery-mode (WGM) resonators and each resonator is also coupled to a yttrium iron garnet (YIG) sphere through the optomagnonic interaction. Phase-dependent single-photon hopping factor couples the two optical resonators and provides an indirect interaction between the two distant magnon modes. We then investigate complete synchronization, φ-synchronization, and quantum phase synchronization using the covariance-matrix formalism as well as also studying the effects of the hopping term on the overall synchronization dynamics of two distant magnon modes. It can be seen that the photon-hopping phase provides an efficient way to control the synchronization dynamics and when it is varied from 0 to π, the magnon trajectories gradually evolve from weakly correlated motion to a highly synchronized state, which is also accompanied by a significant reduction in the synchronization error. The influence of the photon-hopping strength and thermal fluctuations is also investigated, where it can be seen that stronger photon hopping enhances all synchronization measures, while thermal noise weakens the coherent correlations responsible for synchronized dynamics. Our results demonstrate that the phase of the hopping factor offers a simple and effective approach for controlling synchronization dynamics in WGM based coupled cavity optomagnonic systems and also provide a useful route towards coherent control of collective magnon dynamics in such quantum optomganonic devices.