CeFePO: f-d hybridization and quenching of superconductivity
cond-mat.supr-con
/ Authors
M. G. Holder, A. Jesche, P. Lombardo, R. Hayn, D. V. Vyalikh, S. Danzenbächer, K. Kummer, C. Krellner, C. Geibel, Yu. Kucherenko
and 4 more authors
/ Abstract
Being homologue to the new, Fe-based type of high-temperature superconductors, CeFePO exhibits magnetism, Kondo and heavy-fermion phenomena. We experimentally studied the electronic structure of CeFePO by means of angle-resolved photoemission spectroscopy. In particular, contributions of the Ce 4f-derived states and their hybridization to the Fe 3d bands were explored using both symmetry selection rules for excitation and their photoionization cross-section variations as a function of photon energy. It was experimentally found - and later on confirmed by LDA as well as DMFT calculations - that the Ce 4f states hybridize to the Fe 3d states of d_{3z^2-r^2} symmetry near the Fermi level that discloses their participation in the occurring electron-correlation phenomena and provides insight into mechanism of superconductivity in oxopnictides.