We investigate the effect of electronic correlations on the transmission phase of quantum coherent scatterers, considering quantum dots in the Coulomb blockade regime connected to two single-channel leads. We focus on transmission zeros and the associated $\pi$-phase lapses that have been observed in interferometric experiments. We numerically explore two types of models for quantum dots: (i) lattice models with up to eight sites, and (ii) resonant level models with up to six levels. We identify different regimes of parameters where the presence of electronic correlations is responsible for the increase or the decrease of the number of transmission zeros versus electrochemical potential on the dot. We show that within the two models considered, interaction effects do not reproduce the universal behavior of alternating resonances and phase lapses, experimentally observed in many-electron Coulomb blockaded dots.

• Received 20 July 2012

DOI:https://doi.org/10.1103/PhysRevB.88.045419