Nested Quantum Annealing Correction

Understand

We present a general error-correcting scheme for quantum annealing that allows for the encoding of a logical qubit into an arbitrarily large number of physical qubits.

• Given any Ising model optimization problem, the encoding replaces each logical qubit by a complete graph of degree $C$, representing the distance of the error-correcting code.
• A subsequent minor-embedding step then implements the encoding on the underlying hardware graph of the quantum annealer.
• We demonstrate experimentally that the performance of a D-Wave Two quantum annealing device improves as $C$ grows.