The effect of inter-dot Coulomb interaction on the charge and energy transport properties of a five-terminal system consisting of three Coulomb-coupled quantum dots

Abstract

We have studied a 5-terminal system consisting of three single level quantum dots (QDs) that are in contact with their respective reservoirs. In addition to the intra-dot Coulomb interaction, the electron in the dot affected by an inter-dot Coulomb repulsion from its adjacent QD. We describe this system by an Anderson type model Hamiltonian and apply the Greens function method to study the transport properties of the system. Since we are interested in temperatures higher than the Kondo temperature, we use the equations of motion technique to calculate Green’s functions. Numerical analysis shows that there is a correlation between the transport characteristics of the lower and upper dot and we can change the conductivity of the lower dot only by varying the parameters of the upper dot and vice versa. We demonstrated that the middle dot play the role of the switch on/off of this correlation. Also, we investigated the effect of thermoelectric properties. We found that the inter-dot Coulomb interaction can improve the thermoelectric performance of the system.