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arXiv · 1301.1500

Quantum memory for microwave photons in an inhomogeneously broadened spin ensemble

Brian Julsgaard·Cécile Grezes·Patrice Bertet·Klaus Mølmer
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Abstract

We propose a multi-mode quantum memory protocol able to store the quantum state of the field in a microwave resonator into an ensemble of electronic spins. The stored information is protected against inhomogeneous broadening of the spin ensemble by spin-echo techniques resulting in memory times orders of magnitude longer than previously achieved. By calculating the evolution of the first and second moments of the spin-cavity system variables for realistic experimental parameters, we show that a memory based on NV center spins in diamond can store a qubit encoded on the |0> and |1> Fock states of the field with 80% fidelity.

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Brian Julsgaard, Cécile Grezes, Patrice Bertet, Klaus Mølmer. 2013-01-08. Quantum memory for microwave photons in an inhomogeneously broadened spin ensemble. https://doi.org/10.1103/physrevlett.110.250503

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