X-ray diffuse scattering experiments on bismuth based high Tc superconductors

A detailed X-ray diffuse scattering study of the recently found two dimensional (2D) displacive short range order (SRO) superstructure, with doubled periodicity along the orthorhombic a direction from the high T, superconductors Bi2Sr2CaCu2O8+delta (BISCO-2212) is reported. The investigation has been extended to high and low temperatures for optimally doped crystals, to crystals with different doping levels and to the one layer compound Bi2Sr2Cu6+delta (BISCO-2201). The most striking feature is that both, the intensity of the diffuse scattering and the extent of the 2DSRO vary with doping as the critical temperature, T, These findings show that these short range ordering features are of importance for a better understanding of high T-c materials, at least those from the BISCO family. (c) 2007 Published by Elsevier B.V.