Surface and bulk4f-photoemission spectra ofCeIn3and

Abstract

Resonant photoemission spectroscopy was performed on CeIn 3 and CeSn 3 at the 4d-4 f and 3d-4 f core thresholds. Using the different surface sensitivity between the two photon energies, surface and bulk 4 f -photoemission spectra were derived for both compounds. With the noncrossing approximation of the Anderson impurity model, the 4d-4 f resonant spectra together with the surface and bulk spectra were selfconsistently analyzed to obtain the microscopic parameters such as the 4 f -electron energy and the hybridization strength with conduction electrons. The result shows a substantial difference in these parameters between the surface and the bulk, indicating that it is important to take into account the surface effect in analyzing photoemission spectra of Ce compounds. It is also found that the 4 f surface core-level shift is different

Band Calculations for Ce Compounds with AuCu3-Type Crystal Structure on the Basis of Dynamical Mean Field Theory: II. CeIn3 and CeSn3

“…The 4f state hybridizes with 5p states of In or Sn in these compounds. Calculated results generally show reasonable agreement with experimental results for the PES [18][19][20][21][22][23] and inelastic magnetic excitation by neutrons, [24][25][26] although the calculation gives somewhat higher T K for CeIn 3 than that expected from experiments, and gives a lower T K for CeSn 3 when experimental results are examined in detail.…”

“…The PES of CeIn 3 at ambient pressure has been extensively studied in experiments. [21][22][23] A comparison with these experimental results will be made in a later section.…”

“…At first glance, the calculated spectrum is very similar to the spectrum under the 4d − 4f resonance condition, but the experimental spectrum is considered to be a superposition of the surface and bulk contributions. [20][21][22][23] The calculated spectral shape around E F has the characteristics of the bulk component. On the other hand, the binding energy of the deep peak is large compared with the experimentally observed value of about 2.5eV.…”

“…Kim and co-workers have observed the PES at the 4d-4f and 3d-4f resonance thresholds and carefully separated the bulk and surface components. 21,22) The bulk component of the PES has a broad peak with a binding energy 2 eV from E F . The calculated intensity of the Kondo resonance part relative to the SOI side band peak is larger than the experimental value.…”

Electronic structure andf-orbital occupancy in Yb-substituted CeCoIn5

“…For instance, substituting Ag for Cu in YbInCu 4 or In for Sn in CeSn 3 leads to a crossover from the intermediate-valent into the heavy-fermion regime. [4][5][6] In these cases, the substitution onto a site other than the rare-earth site drives the valence of the rare-earth toward 3+. Substitutions onto the rare-earth site have also been made, but usually with a non-magnetic analogue in order to study the cross-over between Anderson lattice and single-impurity model behavior, such as in Yb 1−x Lu x Al 3 , 7 or to introduce scattering into superconducting planes, as in Ce 1−x La x CoIn 5 .…”