Be ready to add a new acronym to your quantum taxonomy: QCD aka Quantum Computer-aided Design.
Researchers at Intel, MIT and University of Toronto, have addressed the question of how one can design and test the performance of the sub-modules of next-generation quantum devices — by using existing quantum computers.
With the increasing size of quantum processors, the sub-modules that constitute the processor will become too large to accurately simulate on a classical computer. Therefore, one would soon have to fabricate and test each new design primitive and parameter choice in time-consuming coordination between design, fabrication, and experimental validation.
To circumvent this slow-down, focusing on superconducting transmon processors as a prominent hardware platform, the team computed the static and dynamic properties of individual and coupled transmons. They showed how the energy spectra of transmons can be obtained by variational hybrid quantum-classical algorithms that are well-suited for near-term noisy quantum computers.
They also numerically demonstrated how single- and two-qubit gates can be realized via Suzuki-Trotter decomposition for digital quantum simulation.
Their methods pave a new way towards designing candidate quantum processors when the demands of calculating sub-module properties exceed the capabilities of classical computing resources.