Title: Quantum-memory-assisted on-demand microwave-optical transduction Show Chinese title

Title: 量子记忆辅助的按需微波光子转换

Abstract: Microwave-optical transducers and quantum memories are fundamental components of quantum repeaters, essential for developing a quantum internet in which solid-state quantum computers serve as nodes interconnected by optical fibers for data transmission. Although both technologies have made significant advancements, the integration of microwave-optical conversion and quantum memory functionalities remains a challenge. Here, we theoretically propose and experimentally demonstrate a memoryenhanced quantum microwave-optical transduction using a Rydberg ensemble. By utilizing a cascaded electromagnetically induced transparency process, we store microwave photons in a highly excited collective state and subsequently convert them into optical photons during the retrieval process. Taking advantage of the optical depth with order of millions for microwave photons in Rydberg ensemble, combined with a minimal storage dephasing rate at the single-photon level, the transducer achieves an areanormalized storage efficiency greater than 90%, a bandwidth of 2.1 MHz, and a noise equivalent temperature as low as 26 K, even in cavity-free conditions. Our findings pave the way for the practical implementation of quantum repeaters based on atomic ensembles in quantum information processing. Show Chinese abstract

Abstract: 微波-光子转换器和量子存储器是量子中继器的基本组件，对于开发量子互联网至关重要，在这种互联网中，固态量子计算机作为节点，通过光纤相互连接以进行数据传输。 尽管这两种技术都取得了显著进展，但微波-光子转换和量子存储功能的集成仍然是一个挑战。 在这里，我们理论上提出并实验上展示了使用里德伯系综的增强存储量子微波-光子转换。 通过利用级联电磁感应透明过程，我们将微波光子存储在一个高度激发的集体状态中，并在检索过程中将其转换为光子。 利用里德伯系综中微波光子的光学深度达到数百万量级，结合单光子水平的最小存储去相位率，该转换器实现了大于90%的面积归一化存储效率，带宽为2.1 MHz，噪声等效温度低至26 K，即使在无腔条件下也是如此。 我们的研究结果为基于原子系综的量子中继器在量子信息处理中的实际应用铺平了道路。