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arXiv · 2604.13900

Dynamic rephasing in a telecom warm vapor quantum memory

Ilse Maillette de Buy Wenniger·Paul Burdekin·Shicheng Zhang·Mikhael J. Rasiah·Anindya Rastogi·Otto T. P. Schmidt·Patrick M. Ledingham·Ian A. Walmsley·S. E. Thomas
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Abstract

The Off-Resonant Cascaded Absorption (ORCA) protocol in warm atomic vapors offers a scalable platform for high-bandwidth, low noise quantum memories, but its coherence time is fundamentally limited by Doppler-induced dephasing. We introduce and experimentally demonstrate a dynamic rephasing protocol that counteracts Doppler dephasing in a telecom-band ORCA quantum memory. By transferring the stored excitation to an auxiliary shelving state, we effectively reverse the accumulated Doppler phase and extend the storage time by a factor of 50 while preserving the memory's GHz bandwidth and low noise. Using this protocol, we then demonstrate on-demand storage and retrieval of four independent time-bin modes within a single warm vapor memory -- showing that Doppler dephasing can alternatively be harnessed for high-dimensional temporal mode processing. Our results establish rephasing in warm atomic vapors as a viable route toward high-bandwidth, temporally multiplexed quantum memories operating at room temperature.

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Ilse Maillette de Buy Wenniger, Paul Burdekin, Shicheng Zhang, Mikhael J. Rasiah, Anindya Rastogi, Otto T. P. Schmidt, Patrick M. Ledingham, Ian A. Walmsley, S. E. Thomas. 2026-04-15. Dynamic rephasing in a telecom warm vapor quantum memory. https://arxiv.org/abs/2604.13900

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