Partial densities of states with polarized oxygen Kα X-ray emission of YBa2Cu3O7−δ
1991; Elsevier BV; Volume: 178; Issue: 1-3 Linguagem: Inglês
10.1016/0921-4534(91)90167-w
ISSN1873-2143
AutoresA. Kottmann, F. Burgäzy, D. J. Lam, Yue‐Wen Fang, P. Lamparter, S. Steeb,
Tópico(s)Advanced Chemical Physics Studies
ResumoO Kα X-ray emission spectra of the high-Tc superconductor YBa2Cu3O7−δ were evaluated in terms of the linear pola rization along the x-,y- and z-direction. These partial spectra represent the electronic densities of states of the valence band with 2px-, 2py- and 2pz-like symmetry. The measurements which are representative for the bulk material were done by using an electron microprobe. The polarization factor of the spectrometer crystal was determined. The O 2px- and O 2py-spectra show a main peak at a binding energy of 1.80 eV and a shoulder at about 4.3 eV as well as a band width of about 8 eV. They differ for binding energies around the shoulder. The O 2pz spectrum which represents the density of states resulting from oxygen p-orbitals perpendicular to the CuO2-planes shows a different shape, a lower integrated intensity, and a smaller energetic breadth compared with the O 2px- and O 2py-spectra. The agreement between recently calculated partial densities of states and the measured X-ray emission spectra is satisfactory.
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