Non-equilibrium Transport and Relaxation in Diffusive Nanowires with Kondo Impurities

TY - GEN

T1 - Non-equilibrium Transport and Relaxation in Diffusive Nanowires with Kondo Impurities

AU - Kroha, Johann

AU - Rosch, Achim

AU - Paaske, Jens

AU - Wölfle, Peter

PY - 2003

Y1 - 2003

N2 - Combining non-equilibrium transport with spectroscopic measurements provides a unique tool for the investigation of the microscopic processes in mesoscopic conductors. Experiments on resistive quantum wires show that the non-equilibrium quasiparticle distribution function f(E,V) as a function of the quasiparticle energy E approximately obeys the scaling property, f(E,V) = f(E/V), if the transport voltage V exceeds a certain crossover scale V^*. This scaling indicates anomalous inelastic relaxation processes to be present. It is demonstrated that the latter can be induced by quantum impurities with a degenerate internal degree of freedom, i.e. by Kondo impurities. We review a perturbative renormalization group method to describe the Kondo effect in an arbitrary stationary non-equilibrium situation as well as in a magnetic field, and show that the experiments are explained in detail by a very low concentration of Kondo impurities, with V^* TK, the Kondo temperature. It is discussed how this provides a possible explanation of the observed low-temperature plateau of the decoherence time in mesoscopic conductors.

AB - Combining non-equilibrium transport with spectroscopic measurements provides a unique tool for the investigation of the microscopic processes in mesoscopic conductors. Experiments on resistive quantum wires show that the non-equilibrium quasiparticle distribution function f(E,V) as a function of the quasiparticle energy E approximately obeys the scaling property, f(E,V) = f(E/V), if the transport voltage V exceeds a certain crossover scale V^*. This scaling indicates anomalous inelastic relaxation processes to be present. It is demonstrated that the latter can be induced by quantum impurities with a degenerate internal degree of freedom, i.e. by Kondo impurities. We review a perturbative renormalization group method to describe the Kondo effect in an arbitrary stationary non-equilibrium situation as well as in a magnetic field, and show that the experiments are explained in detail by a very low concentration of Kondo impurities, with V^* TK, the Kondo temperature. It is discussed how this provides a possible explanation of the observed low-temperature plateau of the decoherence time in mesoscopic conductors.

U2 - 10.1007/978-3-540-44838-9_16

DO - 10.1007/978-3-540-44838-9_16

M3 - Conference article

SN - 1438-4329

VL - 43

SP - 351

EP - 377

JO - Advances in Solid State Physics

JF - Advances in Solid State Physics

ER -