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Orbital-Controlled Superconductivity in f-Electron Systems

Katsunori Kubo·Takashi Hotta
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Abstract

We propose a concept of superconductivity controlled by orbital degree of freedom taking CeMIn5 (M= Co, Rh, and Ir) as typical examples. A microscopic multiorbital model for CeMIn5 is analyzed by fluctuation exchange approximation. Even though the Fermi-surface structure is unchanged, the ground state is found to change significantly among paramagnetic, antiferromagnetic, and d-wave superconducting phases, depending on the dominant orbital component in the band near the Fermi energy. We show that our picture naturally explains the different low-temperature properties of CeMIn5 by carefully analyzing the crystalline electric field states.

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Katsunori Kubo, Takashi Hotta. 2006-07-25. Orbital-Controlled Superconductivity in f-Electron Systems. https://doi.org/10.1143/jpsj.75.083702

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