Quantum interference and electron correlation in charge transport through triangular quantum dot molecules

Abstract

We study the charge transport properties of triangular quantum dot molecules (TQDMs) connected to metallic electrodes, taking into account all correlation functions and relevant charging states. The quantum interference (QI) effect of TQDMs resulting from electron coherent tunneling between quantum dots is revealed and well interpreted by the long distance coherent tunneling mechanism. The spectra of electrical conductance of TQDMs with charge filling from one to six electrons clearly depict the many-body and topological effects. The calculated charge stability diagram for conductance and total occupation numbers matches well with the recent experimental measurements. We also demonstrate that the destructive QI effect on the tunneling current of TQDMs is robust with respect to temperature variation, making the single electron QI transistor feasible at higher temperatures.