Quantum interference effects on the electronic transmission through quantum dot molecules

Abstract

The fabrication and control of devices at nanometric scale emphasizesthe importance of quantum effects on the electronic motion in semiconductor heterostructures. The size of the systems through which the electrons move makes mandatory to take into account their wave-like character. As a consequence, the typical interference effects play an important role. In this chapter the noticeable Fano and Aharonov?Bohm effects in the transmission through a ring of quantum dots threaded by a magnetic flux will be discussed. They arise from the interference of the electron wave function when propagating along several transmission paths. The effects manifest themselves as peaks of high conductance and dips of cancellations of transmission along the ring. The control of the gate potentials applied to quantum dots and the magnetic field threading the ring allow one to tune the energies at whichhigh and low transmissions occur.