Quantum circuit optimization for multiple QPUs using local structure

Understand

Interconnecting clusters of qubits will be an essential element of scaling up future quantum computers.

• Operations between quantum processing units (QPUs) are usually significantly slower and costlier than those within a single QPU, so usage of the interconnect must be carefully managed.
• This is loosely analogous to the need to manage shared caches or memory in classical multi-CPU machines.
• Unlike classical clusters, however, quantum data is subject to the no-cloning theorem, which necessitates a rethinking of cache coherency strategies.