Optomechanical entanglement in a whispering-gallery cavity

Abderrahim Lakhfif, Abdelkader Hidki, Jamal El Qars +1 more

Xianwu Mi, Jiangxiang Bai, Dejun Li

The dynamics of the optomechanical entanglement between optical cavity field modes and a macroscopic mechanical breathing mode in a whispering-gallery cavity as well as the continuous variable entanglement between the phase-quadrature amplitudes of the two whispering-gallery modes have been analysed. Simulated results indicate that under state-of-the-art experimental conditions, optomechanical entanglement is obvious and can occur even at temperatures of above 40 K. Compared with the entanglement of the mechanical oscillator at the ground state temperature, optomechanical entanglement is more intense by several orders of magnitude.

Ni Liu, Jun‐Qi Li, J.-Q. Liang

Bo Zhao, Mei‐Rong Wei, Qi Guo

We propose how to achieve a backscattering-immune quantum system containing a cavity with defects. We find that, by placing a nanoparticle in the evanescent field of the whispering-gallery-mode resonator with proper relative position and size, the impact of backscattering induced by the defect can be almost eliminated completely. This makes it possible to realize backscattering immunity for both quantum entanglement and classical information transmission. We also show that both the degree of optomechanical entanglement and the transmissivity of the resonator can be manipulated by tuning the relative position of the nanoparticle. This work provides insights into the protection and manipulation of quantum and classical resources, which is meaningful for building noise-tolerant optomechanical quantum processors, achieving ideal quantum precision measurements and backscattering-immune integrated quantum photonic circuits.

Hua‐Jun Chen, Jianyong Yang, Deming Zhao +1 more

We theoretically investigate the optical bistability in a composite photonic molecule cavity optomechanical system consisting of two whispering gallery mode microcavities, where one of the optical cavities is optomechanical with a high quality factor, and the other optical cavity is an auxiliary cavity with high cavity dissipation. By controlling the coupling strength J between the two cavities determined by their distance, the decay rate ratio δ of the two cavities, and the pump power P, the optical bistability can be controlled. Further, the transmission spectrum of the signal field can be efficiently attenuated or amplified, depending on the power of a second “gating” (pump) field P, and other parameters. Our study for photonic-molecule optomechanics systems may be a promising candidate for single-photon transistors and pave the way for potential applications in quantum information technologies.

Jindao Tang, Qizhi Cai, Ze-Di Cheng +9 more