Interplay between quantum interference and Kondo effects in nonequilibrium transport through nanoscopic systems

P. ROURA-BAS, L. TOSI, A. A. ALIGIA, AND K. HALLBERG

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Lugar: New York; Año: 2011 vol. 84 p. 73 - 406

1098-0121

We calculate the finite temperature and nonequilibrium electric current through systems described genericallyat low energy by a singlet and two spin doublets for N and N ± 1 electrons, respectively, coupled asymmetricallyto two conducting leads, which allows for destructive interference in the conductance. The model is suitable forstudying transport in a great variety of systems such as aromatic molecules, different geometries of quantum dots,and rings with applied magnetic flux. As a consequence of the interplay between interference and Kondo effect,we find changes by several orders of magnitude in the values of the conductance and its temperature dependenceas the doublet level splitting is changed by some external parameter. The differential conductance at finite bias isnegative for some parameters.