Atom-Photon Spin-Exchange Collisions Mediated by Rydberg Dressing
Atom-Photon Spin-Exchange Collisions Mediated by Rydberg Dressing
复制标题
里德伯敷料介导的原子-光子自旋交换碰撞
DOI：
10.1103/physrevlett.125.143601
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发表时间：
2020
影响因子：
8.6
通讯作者：
You Li
中科院分区：
文献类型：
--
作者：
Yang Fan;Liu Yong-Chun;You Li
我们证明了单光子通过里德堡修饰的原子系综时可以与单个原子交换其自旋态。这种自旋交换碰撞既表现出耗散特征，又表现出相干特征，这取决于相互作用的强度。对于强相互作用，碰撞耗散地将系统驱动到光子与原子的纠缠暗态。在弱相互作用区，散射相干地反转了多光子输入脉冲中单光子的自旋，展示了一般的单光子减去过程。对这一过程的分析处理揭示了提取光子的效率和纯度之间的普遍权衡，这适用于一大类单光子减法器。结果表明，在一种新的相位匹配条件下，可以通过调整散射率来优化这种折衷。
We show that a single photon propagating through a Rydberg-dressed atomic ensemble can exchange its spin state with a single atom. Such a spin-exchange collision exhibits both dissipative and coherent features, depending on the interaction strength. For strong interaction, the collision dissipatively drives the system into an entangled dark state of the photon with an atom. In the weak interaction regime, the scattering coherently flips the spin of a single photon in the multiphoton input pulse, demonstrating a generic single-photon subtracting process. An analytical treatment of this process reveals a universal trade-off between efficiency and purity of the extracted photon, which applies to a wide class of single-photon subtractors. We show that such a trade-off can be optimized by adjusting the scattering rate under a novel phase-matching condition.