Interference Effects on Kondo-Assisted Transport through Double Quantum Dots

We systematically investigate electron transport through double quantum dots with particular emphasis on interference induced via multiple paths of electron propagation. By means of the slave-boson mean-field approximation, we calculate the conductance, the local density of states, the transmission probability in the Kondo regime at zero temperature. It is clarified how the Kondo-assisted transport changes its properties when the system is continuously changed among the serial, parallel and T-shaped double dots. The obtained results for the conductance are explained in terms of the Kondo resonances influenced by interference effects. We also discuss the impacts due to the spin-polarization of ferromagnetic leads.