Liu Jin-Song, Yang Jun-Ya, Liu Hong-Yu, Zhu Ai-Dong
Opt Express. 2020 Jun 8;28(12):18397-18406. doi: 10.1364/OE.395618.
A significantly low value of the single-photon coupling constant is a major challenge in the creation of a single-photon source via photon blockade. Here, we propose a photon blockade scheme composed of a weakly second-order nonlinear medium with an optical parametric amplification in a low-frequency cavity. Unlike the traditional weakly coupled system, the effective coupling strength in the proposed scheme can be significantly higher than the decay rate of the cavity mode. This can be achieved by adjusting the squeezing parameter even if the original coupling strength is weak. The thermal noise of the squeezed cavity mode can be suppressed by a squeezed vacuum field. Using a probability amplitude method, we obtain the optimal condition of photon blockade in the steady-state. By solving the master equation numerically in the steady-state, a strong photon antibunching effect that is consistent with the optimal conditions can be obtained in the cavity with low frequency. Besides, the photon blockade phenomenon and cross-correlation of two cavities can be significantly enhanced under a specific squeezing parameter. Our results may be useful for future studies on the characteristics of photon statistics.
单光子耦合常数的显著低值是通过光子阻塞创建单光子源的一个主要挑战。在此，我们提出一种由具有低频腔中光学参量放大的弱二阶非线性介质组成的光子阻塞方案。与传统的弱耦合系统不同，所提方案中的有效耦合强度可以显著高于腔模的衰减率。即使原始耦合强度较弱，这也可以通过调整压缩参数来实现。压缩腔模的热噪声可以被压缩真空场抑制。使用概率幅方法，我们在稳态下获得了光子阻塞的最优条件。通过在稳态下数值求解主方程，在低频腔中可以获得与最优条件一致的强光子反聚束效应。此外，在特定的压缩参数下，两个腔的光子阻塞现象和互相关可以显著增强。我们的结果可能对未来光子统计特性的研究有用。
