Improving qubit coherence using closed-loop feedback.

Autor: Vepsäläinen A; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA. apvepsala@gmail.com., Winik R; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA., Karamlou AH; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA.; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA., Braumüller J; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA., Paolo AD; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA., Sung Y; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA., Kannan B; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA., Kjaergaard M; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA.; Center for Quantum Devices, University of Copenhagen, Copenhagen, Denmark., Kim DK; MIT Lincoln Laboratory, Lexington, MA, USA., Melville AJ; MIT Lincoln Laboratory, Lexington, MA, USA., Niedzielski BM; MIT Lincoln Laboratory, Lexington, MA, USA., Yoder JL; MIT Lincoln Laboratory, Lexington, MA, USA., Gustavsson S; Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA., Oliver WD; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA.; MIT Lincoln Laboratory, Lexington, MA, USA.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2022 Apr 11; Vol. 13 (1), pp. 1932. Date of Electronic Publication: 2022 Apr 11.
DOI: 10.1038/s41467-022-29287-4
Abstrakt: Superconducting qubits are a promising platform for building a larger-scale quantum processor capable of solving otherwise intractable problems. In order for the processor to reach practical viability, the gate errors need to be further suppressed and remain stable for extended periods of time. With recent advances in qubit control, both single- and two-qubit gate fidelities are now in many cases limited by the coherence times of the qubits. Here we experimentally employ closed-loop feedback to stabilize the frequency fluctuations of a superconducting transmon qubit, thereby increasing its coherence time by 26% and reducing the single-qubit error rate from (8.5 ± 2.1) × 10 -4 to (5.9 ± 0.7) × 10 -4 . Importantly, the resulting high-fidelity operation remains effective even away from the qubit flux-noise insensitive point, significantly increasing the frequency bandwidth over which the qubit can be operated with high fidelity. This approach is helpful in large qubit grids, where frequency crowding and parasitic interactions between the qubits limit their performance.
(© 2022. The Author(s).)
Databáze: MEDLINE
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