Evidences of Mott physics in iron pnictides from x-ray spectroscopy

S. Lafuerza; H. Gretarsson; F. Hardy; T. Wolf; C. Meingast; G. Giovannetti; M. Capone; A. S. Sefat; Y. -J. Kim; P. Glatzel; L. de' Medici

doi:10.1103/physrevb.96.045133

arXiv · 1607.07417

Evidences of Mott physics in iron pnictides from x-ray spectroscopy

S. Lafuerza·H. Gretarsson·F. Hardy·T. Wolf·C. Meingast·G. Giovannetti·M. Capone·A. S. Sefat·Y. -J. Kim·P. Glatzel·L. de' Medici

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Abstract

X-ray emission and absorption spectroscopies are jointly used as fast probes to determine the evolution as a function of doping of the fluctuating local magnetic moments in K- and Cr- hole-doped BaFe2As2. An increase in the local moment with hole-doping is found, supporting the theoretical scenario in which a Mott insulating state that would be realized for half-filled conduction bands has an influence throughout the phase diagram of these iron-pnictides.

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S. Lafuerza, H. Gretarsson, F. Hardy, T. Wolf, C. Meingast, G. Giovannetti, M. Capone, A. S. Sefat, Y. -J. Kim, P. Glatzel, L. de' Medici. 2016-07-25. Evidences of Mott physics in iron pnictides from x-ray spectroscopy. https://doi.org/10.1103/physrevb.96.045133

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