Polarisation-dependent X-ray absorption in high- and low-Tc Bi2Sr2Can-1CunO4+2n superconductors

Summary, in English

Taking advantage of the linear polarisation of synchrotron radiation, the polarisation dependence of the O K and Cu L₃ X-ray absorption edges has been compared for in situ cleaved Bi₂Sr₂CaCu₂O₈ and Bi₂Sr₂CuO₆ single crystals. The X-ray absorption spectra were measured by means of total electron yield detection. The spectra show for both crystals that the lowest unoccupied Cu 3d and O 2p orbitals are dominantly oriented parallel to the a-b plane, but also the presence of a small amount of unoccupied orbitals oriented perpendicular to the a-b plane can be deduced from both the O K and Cu L3 absorption spectra. A shift of the order of 0.5 eV between absorption into the in-plane and the out-of-plane Cu 3d orbitals was measured for the Bi₂Sr₂CaCu₂O₈ crystal, but no such shift was found for the Bi₂Sr₂CuO₆ crystal.

• Author: M. Qvarford; N. L. Saini; J. N. Andersen; R. Nyholm; E. Lundgren; I. Lindau; J. F. van Acker; L. Leonyuk; S. Söderholm; S. A. Flodström
• Department/s: Synchrotron Radiation Research
• Publishing year: 1993-09-01
• Language: English
• Pages: 119-126
• Publication/Series: Physica C: Superconductivity and its Applications
• Volume: 214
• Issue: 1-2
• Links: http://dx.doi.org/10.1016/0921-4534(93)90116-8
• Document type: Journal article
• Publisher: Elsevier
• Status: Published
• ISBN/ISSN/Other: ISSN: 0921-4534