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arXiv · 1708.01919

Fast, noise-free memory for photon synchronization at room temperature

Ran Finkelstein·Eilon Poem·Ohad Michel·Ohr Lahad·Ofer Firstenberg
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Abstract

Future quantum photonic networks require coherent optical memories for synchronizing quantum sources and gates of probabilistic nature. We demonstrate a fast ladder memory (FLAME) mapping the optical field onto the superposition between electronic orbitals of rubidium vapor. Employing a ladder level-system of orbital transitions with nearly degenerate frequencies simultaneously enables high bandwidth, low noise, and long memory lifetime. We store and retrieve 1.7-ns-long pulses, containing 0.5 photons on average, and observe short-time external efficiency of 25%, memory lifetime (${1/e}$) of 86 ns, and below ${10^{-4}}$ added noise photons. Consequently, coupling this memory to a probabilistic source would enhance the on-demand photon generation probability by a factor of 12, the highest number yet reported for a noise-free, room-temperature memory. This paves the way towards the controlled production of large quantum states of light from probabilistic photon sources.

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Ran Finkelstein, Eilon Poem, Ohad Michel, Ohr Lahad, Ofer Firstenberg. 2017-08-06. Fast, noise-free memory for photon synchronization at room temperature. https://doi.org/10.1126/sciadv.aap8598

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