近日，长春理工大学物理学院的杨慧及其研究团队取得一项新进展。经过不懈努力，他们实现了嵌入原子四波混频系统中的单光子和双光子阻塞。相关研究成果发表已于2024年4月1日在国际知名学术期刊《物理评论A》上发表。

本文研究了嵌入二能级原子的非简并四波混频系统中的光子阻塞效应。通过解析计算和数值分析，研究人员发现通过调整系统参数可以实现单光子和双光子的阻塞效应。即(i)当四波混频相互作用和原子-腔耦合强度不相等时，系统可以实现单光子阻塞;(ii)当它们相互一致时，系统可以实现双光子阻塞。

此外，研究人员还详细讨论了不同参数对光子阻塞效应的影响。结果表明，本文所构建的系统不仅能够有效增强单光子的阻塞效果，而且在合理设计的能级结构下，也能轻松实现双光子的阻塞。值得注意的是，光子阻塞的效果与系统参数之间存在着显著的关联。这一研究成果为未来设计单光子和多光子源或器件的实验和实际应用提供了理论参考。

附：英文原文

Title: One-photon and two-photon blockades in a four-wave-mixing system embedded with an atom

Author: Yuanchuan Li, Zhihai Yao, Hui Yang

Issue&Volume: 2024/04/01

Abstract: In this paper, the photon blockade effect in a nondegenerate four-wave-mixing system embedded with a two-level atom has been studied. By using an analytical calculation and numerical analysis, we find that both one-photon and two-photon blockade effects could be realized in this system by adjusting the parameters of the system. That is, (i) when the four-wave-mixing interaction and the atom-cavity coupling strength are not equal, the system can realize a one-photon blockade; (ii) when they are consistent with each other, the system can realize a two-photon blockade. In addition, we also discuss the influence of different parameters on the photon blockade effect in detail. The results show that the system constructed in this paper not only could enhance the one-photon blockade effect decisively, but also could implement a two-photon blockade easily with a well-designed energy-level structure, and evidently the blockade effect depends on the parameters of the system. All the results may provide theoretical references for single-photon and multiphoton sources or devices in designing future experiments and practical applications.

DOI: 10.1103/PhysRevA.109.043702

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.043702