Anderson Model Out of Equilibrium: Time-Dependent Perturbations

The influence of high-frequency fields on transport through a quantum dot is studied in the low-temperature regime. We generalize the noncrossing approximation for the infinite- U Anderson model to the time-dependent case. The dc spectral density shows asymmetric Kondo side peaks due to photon-assisted resonant tunneling. As a consequence, we predict an electron-photon pump at zero bias which is purely based on the Kondo effect. The differential conductance shows resonant side peaks with a characteristic line shape. All the effects are important for a signature of the Kondo effect in quantum dots.