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arXiv · 1510.06565

Towards a spin-ensemble quantum memory for superconducting qubits

C. Grezes·Y. Kubo·B. Julsgaard·T. Umeda·J. Isoya·H. Sumiya·H. Abe·S. Onoda·T. Ohshima·K. Nakamura·I. Diniz·A. Auffeves·V. Jacques·J. -F. Roch·D. Vion·D. Esteve·K. Moelmer·P. Bertet
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Abstract

This article reviews efforts to build a new type of quantum device, which combines an ensemble of electronic spins with long coherence times, and a small-scale superconducting quantum processor. The goal is to store over long times arbitrary qubit states in orthogonal collective modes of the spin-ensemble, and to retrieve them on-demand. We first present the protocol devised for such a multi-mode quantum memory. We then describe a series of experimental results using NV center spins in diamond, which demonstrate its main building blocks: the transfer of arbitrary quantum states from a qubit into the spin ensemble, and the multi-mode retrieval of classical microwave pulses down to the single-photon level with a Hahn-echo like sequence. A reset of the spin memory is implemented in-between two successive sequences using optical repumping of the spins.

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C. Grezes, Y. Kubo, B. Julsgaard, T. Umeda, J. Isoya, H. Sumiya, H. Abe, S. Onoda, T. Ohshima, K. Nakamura, I. Diniz, A. Auffeves, V. Jacques, J. -F. Roch, D. Vion, D. Esteve, K. Moelmer, P. Bertet. 2015-10-22. Towards a spin-ensemble quantum memory for superconducting qubits. https://doi.org/10.1016/j.crhy.2016.07.006

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