Adiabatic pumping in the mixed-valence and Kondo regimes

TL;DR

This paper explores adiabatic pumping in quantum dots within the mixed-valence and Kondo regimes, revealing how tunneling and Friedel phase modulations influence current, including spin-charge separation under magnetic fields.

Contribution

It introduces a detailed analysis of adiabatic pumping mechanisms in strongly correlated quantum dots using the slave-boson mean field approximation, highlighting Coulomb interaction effects.

Findings

Pumped current depends on tunneling barriers and Friedel phase modulation.

Sign of tunneling contribution varies with Coulomb interaction strength.

Spin and charge currents separate under finite magnetic fields in the Kondo regime.

Abstract

We investigate adiabatic pumping through a quantum dot with a single level in the mixed-valence and Kondo regimes using the slave-boson mean field approximation. The pumped current is driven by a gauge potential due to time-dependent tunneling barriers as well as by the modulation of the Friedel phase. The sign of the former contribution depends on the strength of the Coulomb interaction. Under finite magnetic fields, the separation of the spin and charge currents peculiar to the Kondo effect occurs.