A scheme is proposed to enhance the photon blockade effect in a hybrid optomechanical system with a $\Lambda$-type atom driven by the microwave. Through analyzing the conventional and unconventional blockade mechanisms, we find that the enhanced photon blockade effect can be attributed to two aspects: I) the non-resonant coupled $\Lambda$-type atom reconstructs the anharmonic eigenenergy spectrum; II) the microwave driving field promotes the destructive quantum interference for two-photon excitation. By means of the joint enhancement effect, the perfect photon blockade, i.e., the second-order correlation function $g^{(2)}(0)\simeq 0$, can be achieved without the strong single-photon optomechanical coupling as reported in the standard optomechanical system. All the analyses and derivations are further verified via simulating the quantum master equation of the initial Hamiltonian numerically, showing well agreement between analytical and numerical results. Moreover, the optimal parameter relation is given to optimize the photon blockade and maximize the occupancy probability of single-photon excitation at the same time. Our scheme provides a feasible method to engineer a high-quality and efficient single-photon source.

中文翻译：

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通过驱动混合光机械系统中被俘获的Λ型原子来增强光子阻断

提出了一种增强光子阻挡效应的混合光机电系统的方案。 $\Lambda$型原子被微波驱动。通过分析常规和非常规的阻断机理，我们发现增强的光子阻断效应可归因于两个方面：I）非共振耦合$\Lambda$型原子重建非谐本征能谱；II）微波驱动场促进了对双光子激发的破坏性量子干扰。通过联合增强效应，实现了完美的光子阻挡，即二阶相关函数$G^{（2）}（0）\simeq 0$无需标准光学机械系统中报告的强单光子光学机械耦合即可实现。通过数值模拟初始哈密顿量的量子主方程进一步验证了所有分析和推导，表明分析结果与数值结果之间具有很好的一致性。此外，给出了最佳参数关系，以优化光子阻挡并同时最大化单光子激发的占用概率。我们的方案提供了一种可行的方法来设计高质量和高效的单光子源。