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Register a new userSingle-atom single-photon coupling facilitated by atomic-ensemble dark-state mechanisms
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We propose to couple single atomic qubits to photons incident on a cavity containing an atomic ensemble of a different species that mediates the coupling via Rydberg interactions. Subject to a classical field and the cavity field, the ensemble forms a collective dark state which is resonant with the input photon, while excitation of a qubit atom leads to a secondary dark state that splits the cavity resonance. The two different dark state mechanisms yield zero and $pi$ reflection phase shifts and can be used to implement quantum gates between atomic and optical qubits.
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