Conductance of Aharonov-Bohm interferometers embedded with an interacting dot: slave-boson mean-field calculation

We numerically calculate the conductance of a one-dimensional Aharonov-Bohm loop containing a weakly coupled dot. The Coulomb repulsion is taken into account in the dot within the slave-boson mean-field approximation. We avoid the so-called phase locking by attaching an additional lead to the loop. The phase of the electron wavefunction deduced from the Aharonov-Bohm oscillation changes gradually by pi when the Fermi energy sweeps across a transmission resonance in the dot. The asymmetric lineshape of Fano-type resonances is also examined. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.