Three-orbital Kondo effect in single quantum dot system with plural electrons

Research paper by Tomoko Kita, Rui Sakano, Takuma Ohashi, Sei-ichiro Suga

Indexed on: 11 Jul '08Published on: 11 Jul '08Published in: Physics - Strongly Correlated Electrons


We study the Kondo effect and related transport properties in orbitally degenerate vertical quantum dot systems with plural electrons. Applying the non-crossing approximation to the three-orbital Anderson impurity model with the finite Coulomb interaction and Hund-coupling, we investigate the magnetic-field dependence of the conductance and thermopower. We also introduce an additional orbital splitting to take account of the realistic many-body effect in the vertical quantum dot system. It is clarified how the three-orbital Kondo effect influences the transport properties via the modulation of the Kondo temperature and unitary limit of transport quantities due to the change of the symmetry in the system.