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Register a new userLenses as an Atom-Photon Interface: A Semiclassical Model
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Strong interaction between the light field and an atom is often achieved with cavities. Recent experiments have used a different configuration: a propagating light field is strongly focused using a system of lenses, the atom being supposed to sit at the focal position. In reality, this last condition holds only up to some approximation; in particular, at any finite temperature, the atom position fluctuates. We present a formalism that describes the focalized field and the atom sitting at an arbitrary position. As a first application, we show that thermal fluctuations do account for the extinction data reported in M. K. Tey et al., Nature Physics 4, 924 (2008).
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The realization of an efficient quantum optical interface for multi-qubit systems is an outstanding challenge in science and engineering. We demonstrate a method for interfacing neutral atom arrays with optical photons. In our approach, atomic qubits trapped in individually controlled optical tweezers are moved in and out of the near-field of a nanofabricated photonic crystal cavity. With this platform, we demonstrate full quantum control, efficient quantum non-destructive readout, and entanglement of atom pairs strongly coupled to the cavity. By encoding the qubits into long-lived states and employing dynamical decoupling, the entangled state is verified in free space after being transported away from the cavity. The combination of a compact, integrated optical link and entanglement transport paves the way for quantum networking with neutral atom quantum processors.
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