Abstract

Electronic transport properties of two quantum dots side-coupled to a quantum wire are studied by means of the two impurity Anderson Hamiltonian. The conductance is found to be a superposition of Fano and Breit-Wigner resonances as a function of the Fermi energy, when the gate voltages of the quantum dots are slightly different. Under this condition, we analyze the time evolution of a Gaussian-shaped superposition of plane waves incoming from the source lead, and found that the wave packet can be split into three packets at the drain lead. This spatial pattern manifests in a direct way the peculiarities of the conductance in energy space. We conclude that the device acts as a quantum electron splitter. © 2006 The American Physical Society.