Soft x-ray energy-dependent angle-resolved photoemission study of CeIrIn5

Abstract

Soft x-ray energy-dependent angle-resolved photoemission measurementsare performed on the heavy-fermion superconductor CeIrIn5 tostudy the Fermi surface (FS) and the electronic structure near the Fermi level in the ΓMZAplane. The non-dispersive band designated as the Ce 4f7/21final state is found at 280 meV along with the main body of thevalence band consisting of highly dispersive In 5p bands, which arein good qualitative agreement with the band structure calculationbased on the itinerant 4f electron model. Furthermore, we found twoelectron-like and one hole-like cylindrical FSs at the M (A) and Γ (Z)points. The Fermi momenta of the observed FSs are consistent with the de Haas–vanAlphen experiment, while they contradict the stronger anisotropy of the FS along thekzdirection predicted by the band calculation. The results suggeststronger two-dimensionality of the electronic structure of CeIrIn5and point to the need for its theoretical verification.