Photonics Research
Efficient coherent optical storage of multi-dimensional states in cold atom ensembles
Xin Yang, Jinwen Wang, Shuwei Qiu, Yuchen Gu, Jianyi Xu, Xinji Zeng, Mingtao Cao, Yun Chen, Chengyuan Wang, Dong Wei, Fuli Li, Hong Gao
Abstract
Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum networks. In this work, we experimentally demonstrate a high-efficiency storage for multi-dimensional photonic states in path, polarization, and orbital angular momentum (with vector beams serving as the photonic dimensional carriers of polarization and orbital angular momentum) in laser-cooled Rb 87 atom ensembles with cigar shapes. We achieve path-multiplexed storage of two-channel vector beams at the single-photon level, with storage efficiency exceeding 74% for first-order vector beams and 72% for second-order vector beams. Additionally, the storage fidelity surpasses 89% for both types. Furthermore, we achieve a storage time of approximately 7 μs for two-channel vector beams, and the spatial structure and phase information are preserved during storage through performed projection measurements. The results confirm that our system has the capability for optical storage in photon polarization and orbital angular momentum, as well as in a multi-dimensional photon path. These results show significant potential for advancing large-scale repeater-based quantum networks and distributed quantum computing.