Evolution of Magnetic Oxygen States in Sr-Doped LaCoO3

TitleEvolution of Magnetic Oxygen States in Sr-Doped LaCoO3
Publication TypeJournal Article
Year of Publication2012
AuthorsMedling S, Lee Y, Zheng H, Mitchell JF, Freeland JW, Harmon BN, Bridges F
Journal TitlePhysical Review Letters
Volume109
Pages157204
Date Published10
Type of ArticleArticle
ISBN Number0031-9007
Accession NumberWOS:000309590300045
Keywordsab-initio, dichroism, electronic-structure, la1-xsrxcoo3, temperature, transition
Abstract

Magnetism in La1-xSrxCoO3 as a function of doping is investigated with x-ray absorption spectroscopy and x-ray magnetic circular dicrhoism at the O K edge, and corresponding first principles electronic structure calculations. For small x, the spectra are consistent with the formation of ferromagnetic clusters occurring within a nonmagnetic insulating matrix. Sr-induced, magnetic O-hole states form just above E-F and grow with increasing Sr doping. Density functional calculations for x = 0 yield a nonmagnetic ground state with the observed rhombohedral distortion and indicates that doping introduces holes at the Fermi level in magnetic states with significant O 2p and Co t(2g) character for the undistorted pseudocubic structure. Supercell calculations show stronger magnetism on oxygen atoms having more Sr neighbors.

URL<Go to ISI>://WOS:000309590300045
DOI10.1103/PhysRevLett.109.157204
Alternate JournalPhys. Rev. Lett.