Adiabatic Transport through Quantum Dots with Coulomb Interaction
Janine Splettstoesser
University of Aachen
Friday, 8 April 2011, 10:30
Matfys library
Abstract:
Adiabatic transport (such as pumping) through quantum dot systems
reveals interesting properties due to quantum coherence and Coulomb
interaction effects, which can not directly be found from a study of
the time-independent system.
I will present results on adiabatic pumping through a double dot
coupled to normal metal or ferromagnetic contacts. Tunnel-induced
renormalization effects due to charge fluctuations and tunneling
through thermally excited states can play an important role here. In
the presence of ferromagnetic leads, these effects can lead to an
inverted spin-valve effect or even to a diverging tunneling
magneto-resistance.
On the other hand time-dependent non-linear transport current through
an interacting quantum dot in the single-electron tunneling regime
(SET) combines the study of pumping with the nonlinear bias regime. We
propose an adiabatic transport spectroscopy where a ``time-averaged
stability diagram'' probes interactions, tunnel asymmetries and
changes in the ground state spin-degeneracy.