Local lattice instability and stripes in theCuO2plane of theLa1.85Sr0.15CuO4system by polarized XANES and EXAFS

N. L. Saini, A. Lanzara, H. Oyanagi, H. Yamaguchi, K. Oka, T. Ito, A. Bianconi
1997 Physical Review B (Condensed Matter)  
Temperature-dependent polarized Cu K-edge x-ray absorption has been used to investigate local structural distortions in the CuO 2 plane of the La 1.85 Sr 0.15 CuO 4 system. The Cu-O pair distribution shows the presence of a minority phase containing CuO 6 octahedra characterized by a shorter Cu-O͑apical͒ bond ͑⌬RϳϪ0.1 Å͒ and two longer Cu-O͑planar͒ bonds ͑⌬Rϳϩ0.08 Å͒ and a tilting angle of 16°Ϯ2°. The temperature-dependent distortions show a maximum around T* (ϳ1.6T c ) and a minimum at T c
more » ... minimum at T c ͑ϳ35 K͒. The data show the coexistence of two types of doped charges in different stripes in the superconducting phase.
doi:10.1103/physrevb.55.12759 fatcat:agr3x5gijnglvmemlpih4peh4i