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arXiv · 1806.07094

Deterministic free-space source of single photons using Rydberg atoms

D. Petrosyan·K. Mølmer
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Abstract

We propose an efficient free-space scheme to create single photons in a well-defined spatiotemporal mode. To that end, we first prepare a single source atom in an excited Rydberg state. The source atom interacts with a large ensemble of ground-state atoms via a laser-mediated dipole-dipole exchange interaction. Using an adiabatic passage with a chirped laser pulse, we produce a spatially extended spin wave of a single Rydberg excitation in the ensemble, accompanied by the transition of the source atom to another Rydberg state. The collective atomic excitation can then be converted to a propagating optical photon via a coherent coupling field. In contrast to previous approaches, our single-photon source does not rely on the strong coupling of a single emitter to a resonant cavity, nor does it require the heralding of collective excitation or complete Rydberg blockade of multiple excitations in the atomic ensemble.

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D. Petrosyan, K. Mølmer. 2018-09-21. Deterministic free-space source of single photons using Rydberg atoms. https://doi.org/10.1103/physrevlett.121.123605

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