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arXiv · 1607.05977

A solid-state single-photon filter

L. de Santis·C. Antón·B. Reznychenko·N. Somaschi·G. Coppola·J. Senellart·C. Gómez·A. Lemaître·I. Sagnes·A. G. White·L. Lanco·A. Auffeves·P. Senellart
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Abstract

A strong limitation of linear optical quantum computing is the probabilistic operation of two-quantum bit gates based on the coalescence of indistinguishable photons. A route to deterministic operation is to exploit the single-photon nonlinearity of an atomic transition. Through engineering of the atom-photon interaction, phase shifters, photon filters and photon- photon gates have been demonstrated with natural atoms. Proofs of concept have been reported with semiconductor quantum dots, yet limited by inefficient atom-photon interfaces and dephasing. Here we report on a highly efficient single-photon filter based on a large optical non-linearity at the single photon level, in a near-optimal quantum-dot cavity interface. When probed with coherent light wavepackets, the device shows a record nonlinearity threshold around $0.3 \pm 0.1$ incident photons. We demonstrate that directly reflected pulses consist of 80% single-photon Fock state and that the two- and three-photon components are strongly suppressed compared to the single-photon one.

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L. de Santis, C. Antón, B. Reznychenko, N. Somaschi, G. Coppola, J. Senellart, C. Gómez, A. Lemaître, I. Sagnes, A. G. White, L. Lanco, A. Auffeves, P. Senellart. 2016-07-20. A solid-state single-photon filter. https://doi.org/10.1038/nnano.2017.85

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