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Numerical Renormalization Group Study of Kondo Effect in Unconventional Superconductors

Masashige Matsumoto·Mikito Koga
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Abstract

Orbital degrees of freedom of a Cooper pair play an important role in the unconventional superconductivity. To elucidate the orbital effect in the Kondo problem, we investigated a single magnetic impurity coupled to Cooper pairs with a $p_x +i p_y$ ($d_{x^2-y^2}+id_{xy}$) symmetry using the numerical renormalization group method. It is found that the ground state is always a spin doublet. The analytical solution for the strong coupling limit explicitly shows that the orbital dynamics of the Cooper pair generates the spin 1/2 of the ground state.

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Masashige Matsumoto, Mikito Koga. 2001-09-25. Numerical Renormalization Group Study of Kondo Effect in Unconventional Superconductors. https://doi.org/10.1143/jpsj.70.2860

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