Kondo effect in quantum dots at high voltage: Universality and scaling - art. no. 156802

We examine the properties of a de-biased quantum dot in the Coulomb blockad e regime. For voltages V that are large compared to the Kondo temperature T -K, the physics is governed by the scales V and gamma, where gamma similar toV/ln(2) (V/T-K) is the nonequilibrium decoherence rate induced by the vol tage-driven current. Based on scaling arguments, self-consistent perturbati on theory, and perturbative renormalization group, we argue that due to the large gamma the system can be described by renormalized perturbation theor y in 1/ln(V/T-K) << 1. However, in certain variants of the Kondo problem., two-channel Kondo physics is induced by a large voltage V.