title: Electronic structure of A- and B-site doped lanthanum manganites: a combined X-ray spectroscopic study.
abstract: The electronic properties of a series of colossal magnetoresistance (CMR) compounds, namely LaMnO3, La(1-x)Ba(x)(MnO3 (0.2 < or = x < or = 0.55), La(0.76)Ba(0.24)Mn(0.84)Co(0.16)O3, and La(0.76)Ba(0.24)Mn(0.78)Ni(0.22)O3, have been investigated in a detailed spectroscopic study. A combination of X-ray photoelectron spectroscopy (XPS), X-ray emission spectroscopy (XES), X-ray absorption spectroscopy (XAS), and resonant inelastic X-ray scattering (RIXS) was used to reveal a detailed picture of the electronic structure in the presence of Ba, Co, and Ni doping in different concentrations. The results are compared with available theory. The valence band of La(1-x)()Ba(x)MnO3 (0 < or = x < or = 0.55) is dominated by La 5p, Mn 3d, and O 2p states, and strong hybridization between Mn 3d and O 2p states is present over the whole range of Ba concentrations. Co-doping at the Mn site leads to an increased occupancy of the e(g) states near the Fermi energy and an increase in the XPS valence band intensity between 0.5 and 5 eV, whereas the Ni-doped sample shows a lower density of occupied states near the Fermi energy. The Ni d states are located in a band spanning the energy range of 1.5-5 eV. XAS spectra indicate that the hole doping leads to mixed Mn 3d-O 2p states. Furthermore, RIXS at the Mn L edge has been used to probe d-d transitions and charge-transfer excitations in La(1-x)Ba(x)MnO3.
authors.affiliation: Department of Physics, University of Osnabrück, Barbarastr. 7, D-49069 Osnabrück, Germany. karsten.kuepper@uos.de
authors.forename: K
authors.initials: K
authors.lastname: Kuepper
authors.forename: M C
authors.initials: MC
authors.lastname: Falub
authors.forename: K C
authors.initials: KC
authors.lastname: Prince
authors.forename: V R
authors.initials: VR
authors.lastname: Galakhov
authors.forename: I O
authors.initials: IO
authors.lastname: Troyanchuk
authors.forename: S G
authors.initials: SG
authors.lastname: Chiuzbaian
authors.forename: M
authors.initials: M
authors.lastname: Matteucci
authors.forename: D
authors.initials: D
authors.lastname: Wett
authors.forename: R
authors.initials: R
authors.lastname: Szargan
authors.forename: N A
authors.initials: NA
authors.lastname: Ovechkina
authors.forename: Ya M
authors.initials: YM
authors.lastname: Mukovskii
authors.forename: M
authors.initials: M
authors.lastname: Neumann