Non-Crossing Approximation Study of Multi-Orbital Kondo Effect in Quantum Dot Systems

Tomoko Kita; Rui Sakano; Takuma Ohashi; Sei-ichiro Suga

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Non-Crossing Approximation Study of Multi-Orbital Kondo Effect in Quantum Dot Systems

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

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Abstract

We study the three-orbital Kondo effect in quantum dot (QD) systems by applying the non-crossing approximation to the three-orbital Anderson impurity model. By investigating the tunneling conductance through a QD, we show that the competition between the Hund-coupling and the orbital level-splitting gives rise to characteristic behavior in transport properties. It is found that the Hund-coupling becomes more important in the three-orbital case than in the two-orbital case. We also show that the enhancement of Kondo temperature due to the singlet-triplet mechanism suggested for the two-orbital model tends to be suppressed by the existence of the third orbital.

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Tomoko Kita, Rui Sakano, Takuma Ohashi, Sei-ichiro Suga. 2006-05-10. Non-Crossing Approximation Study of Multi-Orbital Kondo Effect in Quantum Dot Systems. https://arxiv.org/abs/cond-mat/0605285

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