Quantum dot spin effect on the conductance of a quantum wire

A numerically exact calculation of the (formula presented) transport properties of a quantum wire interacting with a lateral two-level quantum dot is presented. The wire conductance is calculated for all different states of charge and spin of the quantum dot. For a dot with two electrons we obtain a...

Descripción completa

Detalles Bibliográficos
Autores principales: Davidovich, M.A., Anda, E.V., Büsser, C.A., Chiappe, G.
Formato: JOUR
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_10980121_v65_n23_p1_Davidovich
Aporte de:
Descripción
Sumario:A numerically exact calculation of the (formula presented) transport properties of a quantum wire interacting with a lateral two-level quantum dot is presented. The wire conductance is calculated for all different states of charge and spin of the quantum dot. For a dot with two electrons we obtain an enhancement of the Kondo temperature at the singlet-triplet transition and a nonuniversal scaling law for its dependence upon the dot energy spacing. We find that the Kondo correlation is stronger for a dot spin (formula presented) than for (formula presented) In both cases the wire current is totally quenched by the Kondo effect. When the dot is in the mixed-valence regime and (formula presented) the wire conductance is partially quenched except in a very small region of gate potential where it reaches the maximum value (formula presented). © 2002 The American Physical Society.