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arXiv · 2211.04415

A Single-Photon-compatible Telecom-C-Band Quantum Memory in a Hot Atomic Gas

S. E. Thomas·S. Sagona-Stophel·Z. Schofield·I. A. Walmsley·P. M. Ledingham
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Abstract

The efficient storage and on-demand retrieval of quantum optical states that are compatible with the telecommunications C-band is a requirement for future terrestrial-based quantum optical networking. Spectrum in the C-band minimises optical fiber-propagation losses, and broad optical bandwidth facilitates high-speed networking protocols. Here we report on a telecommunication wavelength and bandwidth compatible quantum memory. Using the Off-Resonant Cascaded Absorption protocol in hot $^{87}$Rb vapour, we demonstrate a total memory efficiency of $20.90(1)\,\%$ with a Doppler-limited storage time of $1.10(2)\,$ns. We characterise the memory performance with weak coherent states, demonstrating signal-to-noise ratios greater than unity for mean photon number inputs above $4.5(6)\times10^{-6}$ per pulse.

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S. E. Thomas, S. Sagona-Stophel, Z. Schofield, I. A. Walmsley, P. M. Ledingham. 2022-11-08. A Single-Photon-compatible Telecom-C-Band Quantum Memory in a Hot Atomic Gas. https://arxiv.org/abs/2211.04415

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