Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 6: TR: Nanoelectronics II: Spintronics and Magnetotransport
TT 6.1: Vortrag
Montag, 22. März 2010, 14:00–14:15, H19
Transport through an interacting quantum dot tunnel coupled to a ferromagnet with time-dependent magnetisation — •Nina Winkler1, Michele Governale2, and Jürgen König1 — 1Theoretische Physik and CeNIDE · Universität Duisburg-Essen — 2School of Chemical and Physical Sciences · Victoria University of Wellington · New Zealand
We study adiabatic charge and spin pumping in an interacting quantum dot connected
to one normal and one ferromagnetic lead. In general, this setup can work as
a quantum pump when only the direction of the lead magnetisation is varied in time [ 1]. We focus on the adiabatic-pumping regime. To account for a time-dependent lead magnetisation, we generalise a diagrammatic real-time approach for adiabatic pumping through quantum dots with ferromagnetic leads [ 2, 3]. We perform a systematic expansion in both
frequency and tunnel-coupling strength, treating the on-site Coulomb interaction on the quantum dot exactly. We investigate the adiabatic charge and spin transport through the structure when pumping by periodically changing the direction of the lead magnetisation up to second order in the tunnel-coupling strength.
[ 1] M.V. Costache et al. , Phys. Rev. Lett. 97, 216603 (2006).
[ 2] J. Splettstoesser et al. , Phys. Rev. B 74, 085305 (2006).
[ 3] J. Splettstoesser et al. , Phys. Rev. B 77, 195320 (2008).