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arXiv · 0807.1780

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

Tomoko Kita·Rui Sakano·Takuma Ohashi·Sei-ichiro Suga
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Abstract

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.

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Tomoko Kita, Rui Sakano, Takuma Ohashi, Sei-ichiro Suga. 2008-07-11. Three-orbital Kondo effect in single quantum dot system with plural electrons. https://doi.org/10.1143/jpsj.77.094707

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