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arXiv · 1111.4671

A counterfactual Rydberg gate for photons

Juan Carlos Garcia-Escartin·Pedro Chamorro-Posada
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Abstract

Quantum computation with photons requires efficient two photon gates. We put forward a two photon entangling gate which uses an intermediate atomic system. The system includes a single Rydberg atom which can switch on and off photon absorption in an ensemble using the dipole blockade. The gate is based in a counterfactual protocol. The mere possibility of an absorption that can only occur with a vanishing probability steers the photons to the desired final state.

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Juan Carlos Garcia-Escartin, Pedro Chamorro-Posada. 2011-11-20. A counterfactual Rydberg gate for photons. https://doi.org/10.1103/physreva.85.032309

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