Autonomous stabilization of remote entanglement in a cascaded quantum network
Abstract: Remote entanglement between separated qubits is an essential quantum phenomenon and a critical resource for quantum information applications. While it results in nonlocal correlations, it typically has to be achieved through a sequence of local interactions between qubits, followed by their spatial separation. It is thus an intriguing question whether it can be achieved in the steady state, without local qubit-qubit interactions. Here, we report experimental autonomous stabilization of remote entanglement between two superconducting-qubit devices. Combining nonreciprocal waveguide coupling and local driving, we realize distance-independent steady-state remote entanglement. With a new approach for overcoming inevitable disorder, we achieve a concurrence approaching 0.5. Our results set the stage for on-demand entanglement delivery in quantum processors and networks, and for protecting multipartite entanglement in open systems.
Bio: Kaushik is a 3rd year physics graduate student working with Wolfgang Pfaff on developing and improving technologies for quantum networks.