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arXiv · 1708.00981

Kondo effect in the seven-orbital Anderson model hybridized with $Γ_8$ conduction electrons

Takashi Hotta
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Abstract

We clarify the two-channel Kondo effect in the seven-orbital Anderson model hybridized with $Γ_8$ conduction electrons by employing a numerical renormalization group method.From the numerical analysis for the case with two local $f$ electrons, corresponding to Pr$^{3+}$ or U$^{4+}$ ion, we confirm that a residual entropy of $0.5\log 2$, a characteristic of two-channel Kondo phenomena,appears for the local $Γ_3$ non-Kramers doublet state. For further understanding on the $Γ_3$ state, the effective model is constructed on the basis of a $j$-$j$ coupling scheme. Then, we rediscover the two-channel $s$-$d$ model concerning quadrupole degrees of freedom. Finally, we briefly introduce our recent result on the two-channel Kondo effect for the case with three local $f$ electrons.

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Takashi Hotta. 2017-08-03. Kondo effect in the seven-orbital Anderson model hybridized with $Γ_8$ conduction electrons. https://doi.org/10.1016/j.physb.2017.07.064

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