J. Phys. IV France 7 (1997) C2-1089-C2-1091
Non-Homogeneity of the CuO2 Plane of the Oxygen Doped La2CuO4.1 System by Polarized EXAFSN.L. Saini1, A. Lanzara1, A. Bianconi1, J.L. Hazemann2, Y. Soldo2 and D.C. Johnston3
1 Dipartimento di Fisica, Università di Roma "La Sapienza", P.A. Moro 2, 00185 Roma, Italy
2 Laboratoire de Cristallographie CNRS, avenue des Martyrs, 38042 Grenoble, France
3 Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, U.S.A.
Temperature dependent in-plane polarized Cu K-edge extended x-ray absorption fine structure (EXAFS) study has been carried out on a high quality single crystal of oxygen doped La2CuO4.1 (LCO) system to investigate the local structure around Cu. The EXAFS data recorded with high degree of plane polarization and up to high momentum transfer (Q=40 A-1 = 2k) allowed the quantitative determination of the distorted and undistorted Cu planes. The determination of the Cu-O(planar) distances shows presence of minority Cu sites characterized by two longer Cu-O(planar) bonds and a tilting of 15° with the average crystallographic structure at T < Ts - 150 K. The data show the coexistence of localized and itinerant charges trapped into stripes of distorted and undistorted domains within the CuO2 plane.
© EDP Sciences 1997