Electron diffraction and high resolution electron microscopic study of the 20K superconducting phase in the BiSrCuO system

Abstract

Using electron diffraction and high resolution electron microscopy it was shown that the 20K superconductor in the BiSrCuO system has a substructure which is closely related to the Aurivillius phases. It consists of lamellae containing two layers of perovskite like cubes alternating with Bi 2O 2 layers. The real structure is a long period incommensurately modulated superstructure, which can be formed in four orientation variants.