Non-local couplings: A new technique to enhance quantum annealing through distribution

Quantum Annealing has proven to be a powerful tool to tackle several optimizationproblems. However, its performance is severely impacted by the limited connectivityof the underlying quantum hardware, compromising the quantum speedup. In thiswork, we present a novel approach to address these issues, by describing a method toimplement non-local couplings throught the lens of Local Operations and ClassicalCommuncations (LOCC).

Non-local couplings are very versatile, harnessing theconfigurability of distributed quantum networks, which in turn lead to greatenhancement of the physical connectivity of the underlying hardware. Furthermore,the realization of non-local couplings between distrinct quantum annealing processorsactivates the scalability potential of distributed systems, i.e. allowing for a distributedquantum annealing system.

Finally, in a more distant vision, we also show that securemulti-party quantum annealing algorithms are possible, allowing for cooperation ofdistrusting parties through optimization with quantum annealing and a particular typeof non-local couplings.