Evidence for weak electronic correlations in Fe-Pnictides

Journal Article · Thu Jun 11 00:00:00 EDT 2009 · Physical Review B

OSTI ID:972806

Yang, W L; Sorini, A P; Chen, C-C; Moritz, B; Lee, W -S; Vernay, F; Olalde-Velasco, P; Denlinger, J D; Delley, B; Chu, J -H; Analytis, J G; Fisher, I R; Ren, Z A; Yang, J; Lu, W; Zhao, Z X; van den Brink, J; Hussain, Z; Shen, Z -X; Devereaux, T P

Using x-ray absorption and resonant inelastic x-ray scattering, charge dynamics at and near the Fe L edges is investigated in Fe pnictide materials, and contrasted tothat measured in other Fe compounds. It is shown that the XAS and RIXS spectra for 122 and 1111 Fe pnictides are each qualitatively similar to Fe metal. Cluster diagonalization, multiplet, and density-functional calculations show that Coulomb correlations are much smaller than in the cuprates, highlighting the role of Fe metallicity and strong covalency in these materials. Best agreement with experiment is obtained using Hubbard parameters U<~;; 2eV and J ~;; 0.8eV.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: Advanced Light Source Division
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 972806
• Report Number(s): LBNL-2491E; TRN: US1001684
• Journal Information: Physical Review B, Vol. 80, Issue 1; Related Information: Journal Publication Date: July 2009; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75
ABSORPTION
COVALENCE
CUPRATES
PNICTIDES
SCATTERING
SPECTRA
iron pnictide
x-ray absorption
XAS
resonant inelastic x-ray scattering
RIXS
correlation