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

摘要

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.