Shot noise of a quantum dot in the Kondo regime perturbed by ac fields

We have investigated the spectral density of shot noise for the system in Kondo regime irradiated with ac fields on the QD and the two terminals. In the low temperature, strong coupling, and large charging energy regime, the correlation effects influence electron transport significantly. The external ac fields split the Kondo peak to form side peaks, and the locations of the side peaks are dependent on the frequency considerably. The differential shot noise in the Kondo regime is very different from that in the non-interacting QD system. The Kondo effect and photon-assisted tunneling destroy the symmetry of shot noise. Both super-Poissonian and sub-Poissonian shot noise exist in Kondo regime. The asymmetric structure is found more evident in the derivative of shot noise for the photon-electron pumping case. Copyright (C) EPLA, 2008.