The study of the hole distribution in high-T-c 1212-type cuprates via x-ray absorption spectroscopy
Journal
Superconductor Science & Technology
Journal Volume
11
Journal Issue
10
Pages
1028-1031
Date Issued
1998
Author(s)
Chen, J. M.
Abstract
High-resolution O K edge x-ray absorption near-edge structure spectra of the high-Tc cuprates of (Tl0.5Pb0.5)Sr2(Ca1-xY x)Cu2O7 (Tl, Pb-1212), (Hg0.5Pb0.5)Sr2(Ca1-xY x)Cu2O7 (Hg, Pb-1212) and (Cd0.5Pb0.5)Sr2(Ca1-xY x)Cu2O7 (Cd, Pb-1212) were measured by a bulk-sensitive total x-ray fluorescence yield technique using synchrotron radiation. Near the O 1s edge, the pre-edge peak at ∼528.3 eV is ascribed to the transitions to O 2p holes located in the CuO2 planes. The intensity of this pre-edge peak increases with increasing doping level of Ca2+ into the Y3+ sites in Tl, Pb-1212, Hg, Pb-1212 and Cd, Pb-1212. The results can provide insight into the understanding of hole distribution and the role of holes in superconductivity in 1212-type cuprates which may give a direction to the search for new high-Tc materials.
Type
journal article