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arXiv · 1902.07720

Optimal Coherent Filtering for Single Noisy Photons

S. Gao·O. Lazo-Arjona·B. Brecht·K. T. Kaczmarek·S. E. Thomas·J. Nunn·P. M. Ledingham·D. J. Saunders·I. A. Walmsley
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Abstract

We introduce a filter using a noise-free quantum buffer with large optical bandwidth that can both filter temporal-spectral modes, as well as inter-convert them and change their frequency. We show that such quantum buffers optimally filter out temporal-spectral noise; producing identical single-photons from many distinguishable noisy single-photon sources with the minimum required reduction in brightness. We then experimentally demonstrate a noise-free quantum buffer in a warm atomic system that is well matched to quantum dots and can outperform all intensity (incoherent) filtering schemes for increasing indistinguishability.

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S. Gao, O. Lazo-Arjona, B. Brecht, K. T. Kaczmarek, S. E. Thomas, J. Nunn, P. M. Ledingham, D. J. Saunders, I. A. Walmsley. 2019-02-20. Optimal Coherent Filtering for Single Noisy Photons. https://doi.org/10.1103/physrevlett.123.213604

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