Nonequilibrium electron transport through quantum dots in the Kondo regime

Peter Woelfle

Institut fuer Theorie der Kondensierten Materie, Universitaet Karlsruhe, 76128 Karlsruhe, Germany

We discuss electron transport in quantum dot devices under stationary nonequilibrium conditions using Keldysh perturbation theory and renormalization group methods.  In particular we investigate how collective many-body states such as the Kondo resonance state are influenced by a finite current through the dot.  We present cases where the Kondo effect is gradually suppressed, and others where it is generated by the current.  We also show that in coupled quantum dots with two pairs of leads there may exist a strong current-current correlation.

J. Paaske, A. Rosch, P. Woelfle, N. Mason, C.M. Marcus and J. Nygaard, Nature Physics 2, 460 (2006).