Quantitative high-resolution electron microscopy of a high- Tc superconductor Tl 2Ba 2Cu 1O y with the imaging plate

Abstract

A high-resolution electron microscope image of the high- T c superconductor Tl 2Ba 2Cu 1O y was quantitatively observed by using the imaging plate. In order to quantitatively evaluate the difference between the intensity of the observed image and that of calculated images, a residual index R HREM (= Σ| I obs − I cal |/ ΣI obs ) was calcu lated for 743 sampling points in the unit cell projected along the [010] direction. Although it has a rather complicated layered structure, R HREM = 0.0473 was obtained by choosing the experimental parameters and taking into account the partial occupancy of Tl atoms. Based on the analysis of the high-resolution electron microscope image of Tl 2Ba 2Cu 1O y , several requirements for further refinement of crystal structure analysis by quantitative high-resolution microscopy were discussed.