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Polarization-controlled single photons

T. Wilk·S. C. Webster·H. P. Specht·G. Rempe·A. Kuhn
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Abstract

Vacuum-stimulated Raman transitions are driven between two magnetic substates of a rubidium-87 atom strongly coupled to an optical cavity. A magnetic field lifts the degeneracy of these states, and the atom is alternately exposed to laser pulses of two different frequencies. This produces a stream of single photons with alternating circular polarization in a predetermined spatio-temporal mode. MHz repetition rates are possible as no recycling of the atom between photon generations is required. Photon indistinguishability is tested by time-resolved two-photon interference.

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T. Wilk, S. C. Webster, H. P. Specht, G. Rempe, A. Kuhn. 2006-10-26. Polarization-controlled single photons. https://doi.org/10.1103/physrevlett.98.063601

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