1. Photoemission signature of momentum-dependent hybridization in CeCoIn5
- Author
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Antonio Tejeda, Dariusz Kaczorowski, Jozef Spałek, K. Kissner, François Bertran, Julien E. Rault, Jan Minár, Friedrich Reinert, Laurent Nicolaï, Ł. Walczak, Maciej Fidrysiak, Dominik Legut, Marcin Rosmus, P. Starowicz, R. Kurleto, Daniel Gnida, and Andrzej P. Kądzielawa more...
- Subjects
Physics ,Strongly Correlated Electrons (cond-mat.str-el) ,Condensed matter physics ,Photoemission spectroscopy ,f electrons, photoemission, resonant ARPES ,FOS: Physical sciences ,Fermi surface ,Fermi energy ,Angle-resolved photoemission spectroscopy ,Photon energy ,Heavy fermion superconductor ,Brillouin zone ,Condensed Matter - Strongly Correlated Electrons ,Tight Binding model ,Wave vector ,hybridization ,multiple scattering KKR - Abstract
Hybridization between $f$ electrons and conduction bands ($c$-$f$ hybridization) is a driving force for many unusual phenomena. To provide insight into it, systematic studies of CeCoIn$_5$ heavy fermion superconductor have been performed by angle-resolved photoemission spectroscopy (ARPES) in a large angular range at temperature of $T=6$ K. The used photon energy of 122 eV corresponds to Ce $4d$-$4f$ resonance. Calculations carried out with relativistic multiple scattering Korringa-Kohn-Rostoker method and one-step model of photoemission yielded realistic simulation of the ARPES spectra indicating that Ce-In surface termination prevails. Surface states, which have been identified in the calculations, contribute significantly to the spectra. Effects of the hybridization strongly depend on wave vector. They include a dispersion of heavy electrons and bands gaining $f$-electron character when approaching Fermi energy. We have also observed a considerable variation of $f$-electron spectral weight at $E_F$, which is normally determined by both matrix element effects and wave vector dependent $c$-$f$ hybridization. Fermi surface scans covering a few Brillouin zones revealed large matrix element effects. A symmetrization of experimental Fermi surface, which reduces matrix element contribution, yielded a specific variation of $4f$-electron enhanced spectral intensity at $E_F$ around $\bar{\Gamma}$ and $\bar{M}$ points. Tight-binding approximation calculations for Ce-In plane provided the same universal distribution of $4f$-electron density for a range of values of the parameters used in the model., Comment: 15 pages, 9 figures more...
- Published
- 2021
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