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arXiv · 2110.02663

Significant enhancement in refrigeration and entanglement in auxiliary-cavity-assisted optomechanical systems

Deng-Gao Lai·Wei Qin·Bang-Pin Hou·Adam Miranowicz·Franco Nori
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Abstract

We propose how to achieve significantly enhanced quantum refrigeration and entanglement by coupling a pumped auxiliary cavity to an optomechanical cavity. We obtain both analytical and numerical results, and find optimal-refrigeration and -entanglement conditions under the auxiliary-cavity-assisted (ACA) mechanism. Our method leads to a giant amplification in the net refrigeration rate, and reveals that the ACA entanglement has a much stronger noise-tolerant ability in comparison with the unassisted case. By appropriately designing the ACA mechanism, an effective mechanical susceptibility can be well adjusted, and a genuine tripartite entanglement of cooling-cavity photons, auxiliary-cavity photons, and phonons could be generated. Specifically, we show that both optomechanical refrigeration and entanglement can be greatly enhanced for the blue-detuned driving of the auxiliary cavity but suppressed for the red-detuned case. Our work paves a way towards further quantum control of macroscopic mechanical systems and the enhancement and protection of fragile quantum resources.

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Deng-Gao Lai, Wei Qin, Bang-Pin Hou, Adam Miranowicz, Franco Nori. 2021-10-06. Significant enhancement in refrigeration and entanglement in auxiliary-cavity-assisted optomechanical systems. https://doi.org/10.1103/physreva.104.043521

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