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arXiv · 1808.01565

Multiplexed storage and real-time manipulation based on a multiple-degree-of-freedom quantum memory

Tian-Shu Yang·Zong-Quan Zhou·Yi-Lin Hua·Xiao Liu·Zong-Feng Li·Pei-Yun Li·Yu Ma·Chao Liu·Peng-Jun Liang·Xue Li·Yi-Xin Xiao·Jun Hu·Chuan-Feng Li·Guang-Can Guo
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Abstract

The faithful storage and coherent manipulation of quantum states with matter-systems enable the construction of large-scale quantum networks based on quantum repeater. To achieve useful communication rates, highly multimode quantum memories will be required to construct a multiplexed quantum repeater. Here, we present the first demonstration of the on-demand storage of orbital-angular-momentum states with weak coherent pulses at the single-photon-level in a rare-earth-ion doped crystal. Through the combination of this spatial degree-of-freedom with temporal and spectral degrees of freedom, we create a multiple-degree-of-freedom memory with high multimode capacity. This device can serve as a quantum mode converter with high fidelity, which is the fundamental requirements for the construction of a multiplexed quantum repeater. This device further enables essentially arbitrary spectral and temporal manipulations of spatial-qutrit-encoded photonic pulses in real-time. Therefore, the developed quantum memory can serve as a building block for scalable photonic quantum information processing architectures.

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Tian-Shu Yang, Zong-Quan Zhou, Yi-Lin Hua, Xiao Liu, Zong-Feng Li, Pei-Yun Li, Yu Ma, Chao Liu, Peng-Jun Liang, Xue Li, Yi-Xin Xiao, Jun Hu, Chuan-Feng Li, Guang-Can Guo. 2018-08-05. Multiplexed storage and real-time manipulation based on a multiple-degree-of-freedom quantum memory. https://doi.org/10.1038/s41467-018-05669-5

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