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arXiv · 1504.02220

Storage and retrieval of microwave fields at the single-photon level in a spin ensemble

C. Grezes·B. Julsgaard·Y. Kubo·W. L. Ma·M. Stern·A. Bienfait·K. Nakamura·J. Isoya·S. Onoda·T. Ohshima·V. Jacques·D. Vion·D. Esteve·R. B. Liu·K. Mølmer·P. Bertet
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Abstract

We report the storage of microwave pulses at the single-photon level in a spin-ensemble memory consisting of $10^{10}$ NV centers in a diamond crystal coupled to a superconducting LC resonator. The energy of the signal, retrieved $100\, \mu \mathrm{s}$ later by spin-echo techniques, reaches $0.3\%$ of the energy absorbed by the spins, and this storage efficiency is quantitatively accounted for by simulations. This figure of merit is sufficient to envision first implementations of a quantum memory for superconducting qubits.

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C. Grezes, B. Julsgaard, Y. Kubo, W. L. Ma, M. Stern, A. Bienfait, K. Nakamura, J. Isoya, S. Onoda, T. Ohshima, V. Jacques, D. Vion, D. Esteve, R. B. Liu, K. Mølmer, P. Bertet. 2015-04-09. Storage and retrieval of microwave fields at the single-photon level in a spin ensemble. https://doi.org/10.1103/physreva.92.020301

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