Similarity of crystalline structure of BSCCO single crystal and multi-layer film

Abstract

Bi2Sr2CaCu2Oy single crystal was studied by means of high-resolution X-ray diffraction and the local work function measurement with scanning tunneling microscope (STM). The results show that the single crystal is natively inhomogeneous. The rocking curve of 00l reflection indicates that the c-axis lattice constant of the crystal varies in a narrow range, clearly showing a multi-layer character. The reflectivity measurement supports this result. It shows an obvious multi-layer character too. The small angle scattering indicates that although the c-axis lattice constant is little different in the crystal, it shows a long period of about 340 A. The local work function measurement with STM demonstrates that the crystal is inhomogeneous. Some part in the crystal acts like thin film and some part like substrate, supporting the results of X-ray analyses.