Abstract
Local structure of plane of the superconducting (Bi2212) crystal at the optimum doping has been investigated by in-plane polarized Cu K-edge x-ray-absorption spectroscopy. We have determined the quadrupole character of the transition in the x-ray-absorption near-edge spectra by rotation of the in-plane polarization geometry by 45° from the Cu-O-Cu direction. The nonzero intensity of this transition in the polarization vector parallel to the Cu-O-Cu direction indicates local structural distortion of the square plane. The statistical distribution of the instantaneous Cu-O bonds is determined by polarized extended x-ray-absorption fine structure and discussed.
- Received 22 October 1997
DOI:https://doi.org/10.1103/PhysRevB.58.11768
©1998 American Physical Society