Professor Chris Van de Walle is one of the DOE-funded quantum sciences researchers

C2QA

The world got its first taste of the power of quantum computing in 2019 when a 53-qubit computer demonstrated quantum supremacy by being the first quantum computer to outpace a classical supercomputer. But that was only just the beginning — a starting block from which researchers have been racing to improve coherence, increase fault tolerance, provide error correction and minimize noise in the upcoming iterations of quantum computers.

Materials scientist Chris Van de Walle is one of those researchers, and he’s joining forces with a collaboration led by Brookhaven Laboratory to co-design — simultaneously design hardware and software — for quantum computers. Called the Co-design Center for Quantum Advantage (C2QA), its mission is to develop a quantum computer that can “outperform a classical computer on a useful task.”

In the subatomic quantum world, the quality of the material hosting quantum behaviors is of major importance. Point defects, such as tiny impurities or vacancies where particles should be, are enough to cause decoherence.

“Understanding those processes that cause decoherence and identifying the defects that are responsible is essential for improving coherence,” commented Van de Walle, whose group performs atomistic calculations that will elucidate the defects and mechanisms.

But not all defects are bad, Van de Walle said. Research will also involve the design and development of defects that can act as “qubits” in a quantum computer ― the analog of the bits in a classical computer. His work is part of C2QA’s effort to increase robustness and pave the way toward scalability.

Achieving the goals of each center will require intense multidisciplinary effort, an approach that the UCSB researchers know well.

“Progress in this exciting and rapidly evolving area requires collaboration and interdisciplinary work, which UCSB is rightly famous for,” Van de Walle said. The researchers will also be able to leverage existing facilities and relationships within the UCSB Quantum Foundry — an NSF-funded collaborative center — as well as the wide and deep pool of quantum research at the university.