title: Kondo interactions from band reconstruction in YbInCu(4).
abstract: We combine resonant inelastic x-ray scattering and model calculations in the Kondo lattice compound YbInCu_{4}, a system characterized by a dramatic increase in Kondo temperature and associated valence fluctuations below a first-order valence transition at T≃42  K. The bulk-sensitive, element-specific, and valence-projected charge excitation spectra reveal an unusual quasigap in the Yb-derived state density which drives an instability of the electronic structure and renormalizes the low-energy effective Hamiltonian at the transition. Our results provide long-sought experimental evidence for a link between temperature-driven changes in the low-energy Kondo scale and the higher-energy electronic structure of this system.
authors: National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
authors: I
authors: I
authors: Jarrige
authors: Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
authors: A
authors: A
authors: Kotani
authors: RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan.
authors: H
authors: H
authors: Yamaoka
authors: Quantum Beam Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Japan.
authors: N
authors: N
authors: Tsujii
authors: Japan Atomic Energy Agency, SPring-8, Sayo, Hyogo 679-5148, Japan.
authors: K
authors: K
authors: Ishii
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: M
authors: M
authors: Upton
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: D
authors: D
authors: Casa
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: J
authors: J
authors: Kim
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: T
authors: T
authors: Gog
authors: Department of Physics and Institute for Materials Science, University of Connecticut, Storrs, Connecticut 06269, USA.
authors: J N
authors: JN
authors: Hancock