Towards a quantum repeater with trapped Yb+ ions in an optical cavity

In a quantum network where entangled photons are used as travelling qubits, a critical challenge is in overcoming the absorption loss of optical fibers. One promising approach is to use quantum repeaters to ‘purify’ the state of photons after a certain optical path length by utilizing matter qubits. Such a node is necessary to scale the size of a distributed quantum computer, and quantum communication networks.

We have designed, and are constructing such a repeater node where a sub-millimeter optical cavity can be integrated into a linear Paul trap. Utilization of Purcell effect will allow us efficient extraction, and injection of entangled photons into the fiber-optic network. Furthermore, our system offers independent access to all vibrational modes of ions, enabling us to work directly with the ionic memory qubits. We will share our recent experimental progress, and the challenges we are addressing.