Progress towards an efficient quantum network with rubidium atoms

Achieving an efficient quantum link between multiple quantum processors is a challenging task

that enables distributed quantum computation and sensing based on a modular architecture.

Here, we report progress towards achieving such a network based on remote entanglement

between two Rb atoms. In order to achieve a high generation rate of atom-atom entanglement,

we maximize the collection efficiency of the photons scattered by the atoms. We discuss an

asymmetric optical cavity and compare its performance with free-space geometries, i.e. lenses

and parabolic mirrors with large numerical aperture. A near-concentric cavity allows for direct

cooling and trapping of the atoms inside the cavity and enhances the photon collection

efficiency significantly. We estimate that a remote entanglement generation rate of more than

1000 (1/s) is feasible with the proposed scheme.

In addition to maximizing the rate, we are building the core of the setup on a chip by using

millimeter-size optics. With the pre-aligned optics on the chip and fiber-coupled out of the

vacuum chamber, the assembly can function as a plug-and-play quantum repeater node, an

essential tool to establish a fully quantum network