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arXiv · 2403.01179

Optomechanical cooling with simultaneous intracavity and extracavity squeezed light

S. S. Zheng·F. X. Sun·M. Asjad·G. W. Zhang·J. Huo·J. Li·J. Zhou·Z. Ma·Q. Y. He
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Abstract

We propose a novel and experimentally feasible approach to achieve high-efficiency ground-state cooling of a mechanical oscillator in an optomechanical system under the deeply unresolved sideband condition with the assistance of both intracavity and extracavity squeezing. In the scheme, a degenerate optical parametric amplifier is placed inside the optical cavity, generating the intracavity squeezing; besides, the optical cavity is driven by externally generated squeezing light, namely the extracavity squeezing. The quantum interference effect generated by intracavity squeezing and extracavity squeezing can completely suppress the non-resonant Stokes heating process while greatly enhancing the anti-Stokes cooling process. Therefore, the joint-squeezing scheme is capable of cooling the mechanical oscillators to their quantum ground state in a regime far away from the resolved sideband condition. Compared with other traditional optomechanical cooling schemes, the single-photon cooling rate in this joint-squeezing scheme can be tremendously enlarged by nearly three orders of magnitude. At the same time, the coupling strength required to achieve ground-state cooling can be significantly reduced. This scheme is promising for cooling large-mass and low-frequency mechanical oscillators, which provides a prerequisite for preparing and manipulating non-classical states in macroscopic quantum systems and lays a significant foundation for quantum manipulation.

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S. S. Zheng, F. X. Sun, M. Asjad, G. W. Zhang, J. Huo, J. Li, J. Zhou, Z. Ma, Q. Y. He. 2024-03-02. Optomechanical cooling with simultaneous intracavity and extracavity squeezed light. https://doi.org/10.1103/physreva.110.063520

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