Electronic transport through a benzene-shaped quantum dots system.

ABSTRACT

Based on the nonequilibrium Green function method, quantum transport through a benzene-shaped quantum dots system is studied. It is shown that the conductance spectrum is sensitive to the arrangement of energy levels of dots. When the energy levels of dots are mismatched, the conductance shows apparent asymmetric structure and striking novel conductance dips appear due to the interference between two distinct paths. The differential conductance as a function of magnetic flux always exhibits 2pi period. An overall suppression of differential conductance emerges for the condition that the levels of dots are all aligned and phi = (2n + 1)pi (n is an integer). In addition, the influence of temperature on the differential conductance is presented.