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Superconductivity in the Orbital Degenerate Model for Heavy Fermion Systems

Tetsuya Takimoto·Takashi Hotta·Kazuo Ueda
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Abstract

Magnetism and superconductivity of new heavy fermion compounds CeTIn$_5$ (T=Co, Rh and Ir) are investigated by applying fluctuation exchange approximation to an orbital degenerate Hubbard model. The superconducting phase with $d_{x^2-y^2}$-symmetry is found to appear next to the antiferromagnetic phase with increasing the orbital splitting energy. The present theory suggests that the orbital splitting energy plays a key role of controlling parameter for the quantum phase transitions in the heavy fermion system.

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Tetsuya Takimoto, Takashi Hotta, Kazuo Ueda. 2002-12-19. Superconductivity in the Orbital Degenerate Model for Heavy Fermion Systems. https://doi.org/10.1088/0953-8984%2F15%2F28%2F329

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