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  • Open Access

Spin relaxation in a single-electron bilayer graphene quantum dot

Lin Wang and Guido Burkard*

  • *Contact author: guido.burkard@uni-konstanz.de
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Phys. Rev. Research 7, 043061 – Published 16 October, 2025

DOI: https://doi.org/10.1103/j6cp-6m5j

Abstract

We study the spin relaxation in a single-electron bilayer graphene quantum dot due to the spin-orbit coupling. The spin relaxation is assisted by the emission of acoustic phonons via the bond-length change and deformation potential mechanisms and 1/f charge noise. In the perpendicular magnetic-field dependence of the spin relaxation rate T1−1, we predict a monotonic increase of T1−1 at higher fields where the electron-phonon coupling via the deformation potential plays a dominant role in spin relaxation. We show a less pronounced dip in T1−1 at lower magnetic fields due to the competition between the electron-phonon coupling due to bond-length change and 1/f charge noise. Finally, detailed comparisons of the magnetic-field dependence of the spin relaxation with the existing experiments by Banszerus et al. [Nat. Commun. 13, 3637 (2022)] and Gächter et al. [PRX Quantum 3, 020343 (2022)] are reported.

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Phys. Rev. Research 7, 043061– Published 16 October, 2025
  • Received 11 April 2025
  • Accepted 18 September 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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