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arXiv · 0808.3603

Heralded single-magnon quantum memory for photon polarization states

Haruka Tanji·Saikat Ghosh·Jonathan Simon·Benjamin Bloom·Vladan Vuletić
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Abstract

We demonstrate a heralded quantum memory based on mapping of a photon polarization state onto a single collective-spin excitation (magnon) shared between two spatially overlapped atomic ensembles. The polarization fidelity is measured by quantum state tomography to be above 90(2)% for any input polarization, which far exceeds the classical limit of 2/3. The process also constitutes a quantum non-destructive probe that detects and regenerates a photon without touching its - potentially undetermined - polarization.

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Haruka Tanji, Saikat Ghosh, Jonathan Simon, Benjamin Bloom, Vladan Vuletić. 2008-08-27. Heralded single-magnon quantum memory for photon polarization states. https://arxiv.org/abs/0808.3603

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