Nonequilibrium transport in quantum dots in the Kondo regime
Talk
Rosa Lopez
Departement de Physique Theorique, Universite de Geneve
June 8, 2004, 3 p.m.
Sala de Juntes, Ed. Mateu Orfila
The Kondo effect is one of the simplest paradigms of condensed matter physics exhibiting strong correlations. The Kondo effect, the crossover from weak to strong coupling for Tbetween itinerant electrons and localized moments in dilute alloys, appears as the localized spin is screened by the itinerant electrons of the metal by the formation of a singlet state. The Kondo effect occurs in quantum dots as well. When the hybridization between the dot and the leads is very strong and the charging energy is very large the Kondo effect appears due to spin-flip interactions. These interactions open up a new transport channel: the so-called Kondo resonance. Importantly, low-temperature transport experiments, both in the linear and non-linear regimes, in quantum dots allow for an unprecedented control on the parameters governing the Kondo effect.
In this work we investigate both the spin and charge transport in quantum dots in the Kondo regime. We discuss for example, the Kondo effect in quantum dots attached to ferromagnetic leads, the two-impurity Kondo problem in serial and parallel quantum dots and the so-called photon-assited Kondo effect.