Theoretical investigations of transport through a Kondo dot with a side-coupled noninteracting quantum-dot array

Abstract

Based on the slave boson approach and the Keldysh Green’s function technique, we investigate theoretically the transport properties of a mesoscopic structure consisting of a Kondo quantum dot with a side-coupled noninteracting quantum-dot array at zero temperature, in which only the Kondo dot is coupled to the leads. When the interdot coupling strengths inside the sided-coupled noninteracting quantum-dot array are compared with the Kondo temperature of the single Kondo dot, the local density of states (LDOS) may be decomposed into one Breit–Wigner and multiple Fano line shapes due to the Fano–Kondo interactions when the appropriate system parameters are considered. The odd–even parity of the linear conductance is also found with the number of side-coupled quantum dots in the array changing, in which the energy levels of quantum dots are pinned at the Fermi energy in the leads. The odd–even parity is broken when the energy levels of side-coupled quantum dots in the quantum array depart from the Fermi energy.