Harnessing many-body spin environment for long coherence storage and high-fidelity single-shot qubit readout.

Autor: Gillard G; Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH, UK. g.gillard@sheffield.ac.uk., Clarke E; Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, S1 3JD, UK., Chekhovich EA; Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH, UK. e.chekhovich@sheffield.ac.uk.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2022 Jul 13; Vol. 13 (1), pp. 4048. Date of Electronic Publication: 2022 Jul 13.
DOI: 10.1038/s41467-022-31618-4
Abstrakt: There is a growing interest in hybrid solid-state quantum systems where nuclear spins, interfaced to the electron spin qubit, are used as quantum memory or qubit register. These approaches require long nuclear spin coherence, which until now seemed impossible owing to the disruptive effect of the electron spin. Here we study InGaAs semiconductor quantum dots, demonstrating millisecond-long collective nuclear spin coherence even under inhomogeneous coupling to the electron central spin. We show that the underlying decoherence mechanism is spectral diffusion induced by a fluctuating electron spin. These results provide new understanding of the many-body coherence in central spin systems, required for development of electron-nuclear spin qubits. As a demonstration, we implement a conditional gate that encodes electron spin state onto collective nuclear spin coherence, and use it for a single-shot readout of the electron spin qubit with >99% fidelity.
(© 2022. The Author(s).)
Databáze: MEDLINE
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