Department of Physics & Astronomy
University of New Mexico

Physics and Astronomy Colloquium

Precision tomography of silicon donor qubits at the threshold of fault tolerance

Presented by Robin Blume-Kohout, Sandia

On January 19, 2022, the cover of Nature announced "Silicon qubits cross key error-correction threshold for quantum computing"1. I'll explain [some of] the science behind this "Big, If True!" claim, and its context within the current explosive growth of quantum computing science and technology. In that issue of Nature, three independent papers reported broadly similar experimental demonstrations. I'll focus on one of them2, co-authored by experimentalists from UNSW (Sydney) and theorists from Sandia's Quantum Performance Lab (QPL). I'll explain the basic physics of the 3-qubit electronuclear device created at UNSW, and then I'll explain how we (the QPL) achieved complete, precise characterization of six logic gates on two donor-atom nuclear spin qubits, to demonstrate error rates below 1%.


3:30 pm, Friday, April 8, 2022


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