Kondo-Dicke resonances in electronic transport through triple quantum dots

Electronic transport through a triple quantum dot system, with only a single dot coupled directly to external leads, is considered theoretically. The model includes Coulomb correlations in the central dot, while such correlations in the two side-coupled dots are omitted. The infinite-U mean-field slave-boson approach is used to obtain basic transport characteristics in the Kondo regime. When tuning the position of the side-coupled dots' levels, transition from subradiant to superradiant-like mode (and vice versa) has been found in the spectral function, in analogy to the Dicke effect in atomic physics. Bias dependence of the differential conductance and zero-frequency shot noise is also analyzed.