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arXiv · 2402.14686

Room-temperature ladder-type optical memory compatible with single photons from InGaAs quantum dots

Benjamin Maaß·Norman Vincenz Ewald·Avijit Barua·Stephan Reitzenstein·Janik Wolters
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Abstract

On-demand storage and retrieval of quantum information in coherent light-matter interfaces is a key requirement for future quantum networking and quantum communication applications. Alkali vapor memories offer scalable and robust high-bandwidth storage at high repetition rates which makes them a natural fit to interface with solid-state single-photon sources. Here, we experimentally realize a room-temperature ladder-type atomic vapor memory that operates on the Cs D1 line. We provide a detailed experimental characterization and demonstration of on-demand storage and retrieval of weak coherent laser pulses with 0.06 photons per pulse at a high signal-to-noise ratio of SNR$=830(80)$. The memory achieves a maximum internal storage efficiency of $\eta_{\text{int}}=15(1)\%$ and an estimated $1/e$-storage time of $\tau_{\mathrm{s}}\approx32\,$ns. Benchmark properties for the storage of single photons from inhomogeneously broadened state-of-the-art solid-state emitters are estimated from the performance of the memory. Together with the immediate availability of high-quality InGaAs quantum dots emitting at 895\,nm, these results provide clear prospects for the development of a heterogeneous on-demand quantum light interface.

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Benjamin Maaß, Norman Vincenz Ewald, Avijit Barua, Stephan Reitzenstein, Janik Wolters. 2024-02-22. Room-temperature ladder-type optical memory compatible with single photons from InGaAs quantum dots. https://doi.org/10.1103/physrevapplied.22.044050

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