Coherence of a Driven Electron Spin Qubit Actively Decoupled from Quasistatic Noise

The coherence of electron spin qubits in semiconductor quantum dots suffers mostly from low-frequency noise. During the past decade, efforts have been devoted to mitigate such noise by material engineering, leading to substantial enhancement of the spin dephasing time for an idling qubit. However, t...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Physical review. X 2020-03, Vol.10 (1), p.011060, Article 011060
Hauptverfasser: Nakajima, Takashi, Noiri, Akito, Kawasaki, Kento, Yoneda, Jun, Stano, Peter, Amaha, Shinichi, Otsuka, Tomohiro, Takeda, Kenta, Delbecq, Matthieu R., Allison, Giles, Ludwig, Arne, Wieck, Andreas D., Loss, Daniel, Tarucha, Seigo
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The coherence of electron spin qubits in semiconductor quantum dots suffers mostly from low-frequency noise. During the past decade, efforts have been devoted to mitigate such noise by material engineering, leading to substantial enhancement of the spin dephasing time for an idling qubit. However, the role of the environmental noise during spin manipulation, which determines the control fidelity, is less understood. We demonstrate an electron spin qubit whose coherence in the driven evolution is limited by high-frequency charge noise rather than the quasistatic noise inherent to any semiconductor device. We employ a feedback-control technique to actively suppress the latter, demonstrating aπ-flip gate fidelity as high as99.04±0.23%in a gallium arsenide quantum dot. We show that the driven-evolution coherence is limited by the longitudinal noise at the Rabi frequency, whose spectrum resembles the1/fnoise observed in isotopically purified silicon qubits.
ISSN:2160-3308
2160-3308
DOI:10.1103/PhysRevX.10.011060