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arXiv · 1904.08321

Slow and fast light behavior of single photons from a quantum dot interacting with the excited state hyperfine structure of the Cesium D1-line

Tim Kroh·Janik Wolters·Andreas Ahlrichs·Andreas W. Schell·Alexander Thoma·Stephan Reitzenstein·Johannes S. Wildmann·Eugenio Zallo·Rinaldo Trotta·Armando Rastelli·Oliver G. Schmidt·Oliver Benson
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Abstract

Hybrid interfaces between distinct quantum systems play a major role in the implementation of quantum networks. Quantum states have to be stored in memories to synchronize the photon arrival times for entanglement swapping by projective measurements in quantum repeaters or for entanglement purification. Here, we analyze the distortion of a single photon wave packet propagating through a dispersive and absorptive medium with high spectral resolution. Single photons are generated from a single In(Ga)As quantum dot with its excitonic transition precisely set relative to the Cesium D1 transition. The delay of spectral components of the single photon wave packet with almost Fourier-limited width is investigated in detail with a 200 MHz narrow-band monolithic Fabry-P\'erot resonator. Reflecting the excited state hyperfine structure of Cesium, "slow light" and "fast light" behavior is observed. As a step towards room-temperature alkali vapor memories, quantum dot photons are delayed for 5 ns by strong dispersion between the two 1.17 GHz hyperfine-split excited state transitions. Based on optical pumping on the hyperfine-split ground states, we propose a simple, all-optically controllable delay for synchronization of heralded narrow-band photons in a quantum network.

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Tim Kroh, Janik Wolters, Andreas Ahlrichs, Andreas W. Schell, Alexander Thoma, Stephan Reitzenstein, Johannes S. Wildmann, Eugenio Zallo, Rinaldo Trotta, Armando Rastelli, Oliver G. Schmidt, Oliver Benson. 2019-04-17. Slow and fast light behavior of single photons from a quantum dot interacting with the excited state hyperfine structure of the Cesium D1-line. https://doi.org/10.1038/s41598-019-50062-x

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