arXiv:2110.09597 · PRX Quantum

Multicell Atomic Quantum Memory as a Hardware-Efficient Quantum Repeater Node

C. Li, S. Zhang, Y.-K. Wu, N. Jiang, Y.-F. Pu, L.-M. Duan

Published Oct 12, 2021• 21 citations

Abstract

For scalable quantum communication and networks, a key step is to realize a quantum repeater node that can efficiently connect different segments of atom-photon entanglement using quantum memories.We report a compact and hardware-efficient realization of a quantum repeater node using a single atomic ensemble for multicell quantum memories.A millisecond lifetime is achieved for individual memory cells after suppressing the magnetic-field-induced inhomogeneous broadening and the atomic-motioninduced spin-wave dephasing.Based on these long-lived memory cells, we achieve heralded asynchronous entanglement generation in two quantum repeater segments one after another and then an on-demand entanglement connection of these two repeater segments.As another application of the multicell atomic quantum memory, we further demonstrate storage and on-demand retrieval of heralded atomic spin-wave qubits by implementing a random access quantum memory with individual addressing capacity.This work provides a promising constituent for efficient realization of quantum repeaters for large-scale quantum networks.

DOI: 10.1103/prxquantum.2.040307

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