Towards large-scale superconducting quantum annealers: 2.5D packaging technology and application specific architecture*

Quantum annealing is a promising technique which leverages quantum mechanics to solve hard combinatorial optimization problems. D-Wave Systems Inc. is the first company to commercialize superconducting quantum annealer in 2011 and ship a new machine with 2000 qubits in 2017. However, integration of larger number of qubits as well as improvement of qubit coherence are required for practical applications. In this talk we will overview our technological integration scheme for large-scale superconducting quantum annealers in AIST. The scalability is achieved by QUIP (QUbit, Interposer and Package substrate) structure, which is based on our multi-layer fabrication and multi-chip 2.5D packaging technology, e.g., Through Silicon Via (TSV) and flip-chip bonding. We have also developed an Application Specific Annealing Computing (ASAC) architecture in order to increase the available hardware budget and reduces the cost and time for R&D. In addition, we will show our theoretical researches on superconducting quantum annealers.