KOPS - Das Institutionelle Repositorium der Universität Konstanz

Non-monotonic spin relaxation and decoherence in graphene quantum dots with spin-orbit interactions

Non-monotonic spin relaxation and decoherence in graphene quantum dots with spin-orbit interactions

Zitieren

Dateien zu dieser Ressource

Dateien Größe Format Anzeige

Zu diesem Dokument gibt es keine Dateien.

HACHIYA, Marco O., Guido BURKARD, J. Carlos EGUES, 2014. Non-monotonic spin relaxation and decoherence in graphene quantum dots with spin-orbit interactions. In: Physical Review B. 89(11), 115427. ISSN 1098-0121. eISSN 1550-235X. Available under: doi: 10.1103/PhysRevB.89.115427

@article{Hachiya2014Nonmo-32324, title={Non-monotonic spin relaxation and decoherence in graphene quantum dots with spin-orbit interactions}, year={2014}, doi={10.1103/PhysRevB.89.115427}, number={11}, volume={89}, issn={1098-0121}, journal={Physical Review B}, author={Hachiya, Marco O. and Burkard, Guido and Egues, J. Carlos}, note={Article Number: 115427} }

Hachiya, Marco O. Burkard, Guido We investigate the spin relaxation and decoherence in a single-electron graphene quantum dot with Rashba and intrinsic spin-orbit interactions. We derive an effective spin-phonon Hamiltonian via the Schrieffer-Wolff transformation in order to calculate the spin relaxation time T<sub>1</sub> and decoherence time T<sub>2</sub> within the framework of the Bloch-Redfield theory. In this model, the emergence of a nonmonotonic dependence of T<sub>1</sub> on the external magnetic field is attributed to the Rashba spin-orbit coupling-induced anticrossing of opposite spin states. A rapid decrease of T<sub>1</sub> occurs when the spin and orbital relaxation rates become comparable in the vicinity of the spin-mixing energy-level anticrossing. By contrast, the intrinsic spin-orbit interaction leads to a monotonic magnetic field dependence of the spin relaxation rate which is caused solely by the direct spin-phonon coupling mechanism. Within our model, we demonstrate that the decoherence time T<sub>2</sub>≃2T<sub>1</sub> is dominated by relaxation processes for the electron-phonon coupling mechanisms in graphene up to leading order in the spin-orbit interaction. Moreover, we show that the energy anticrossing also leads to a vanishing pure spin dephasing rate for these states for a super-Ohmic bath. Egues, J. Carlos Burkard, Guido Egues, J. Carlos Hachiya, Marco O. 2015-12-03T10:35:00Z Non-monotonic spin relaxation and decoherence in graphene quantum dots with spin-orbit interactions 2015-12-03T10:35:00Z eng 2014

Das Dokument erscheint in:

KOPS Suche


Stöbern

Mein Benutzerkonto