Speaker: Jason Petta
Title: High-fidelity quantum control and readout of spins in silicon
Abstract: Electron spins are excellent candidates for solid-state quantum computing owing to their exceptionally long quantum coherence times . In the past few years, silicon spin qubits have transitioned from basic demonstrations of quantum control to high-fidelity gate operations that may be sufficient to support quantum error correction. I will describe recent experiments where we achieve single-spin initialisation and readout with errors <1%, single-qubit control with a fidelity exceeding 99.95%, and a two-qubit gate with a fidelity of 99.8% [2,3]. These results pave the way for more advanced spin qubit implementations using industrially fabricated silicon quantum devices.
 G. Burkard, T. D. Ladd, J. M. Nichol, A. Pan & J. R. Petta. Semiconductor spin qubits. Rev. Mod. Phys. (in press).
 A. R. Mills, C. R. Guinn, M. M. Feldman, A. J. Sigillito, M. J. Gullans, M. Rakher, J. Kerckhoff, C. A. C. Jackson & J. R. Petta. High-fidelity state preparation, quantum control, and readout of an isotopically enriched silicon spin qubit. Phys. Rev. Appl. (in review).
 A. R. Mills, C. R. Guinn, M. J. Gullans, A. J. Sigillito, M. M. Feldman, E. Nielsen & J. R. Petta. Two-qubit silicon quantum processor with operation fidelity exceeding 99%. Sci. Adv. 8:abn5130 (2022).
Bio: Jason Petta is a professor of physics at UCLA. He received a PhD in physics from Cornell University in 2003. As a postdoctoral fellow at Harvard, Petta had a leading role in a series of experiments demonstrating trapping and detection of single electrons, as well as a seminal experiment demonstrating coherent control of two-electron spin states. Recent advances in Petta’s group include the fabrication of a scalable quantum dot device architecture in silicon, shuttling a single charge down an array of silicon quantum dots, and the demonstration of a high-fidelity two-qubit gate for spins in silicon. Petta’s group has also developed hybrid quantum devices incorporating semiconducting and superconducting elements. Physics breakthroughs include the demonstration of strong coupling of a single charge to a single photon, strong coupling of a single spin to a single photon, and the coupling of two spins separated by 4 mm using microwave-frequency photons.
Professor Petta is a recipient of the Presidential Early Career Award for Scientists and Engineers, a National Science Foundation CAREER Award, the McMillan Award, the American Association for the Advancement of Science Newcomb Cleveland prize, and the Lee–Osheroff–Richardson prize. Petta was a Moore Foundation Experimental Investigator in Quantum Materials from 2014 to 2020. Petta was recently elected as a Fellow of the American Physical Society and Fellow of the American Association for the Advancement of Science.
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