Polarizing Microscopic Observation of the Superconducting Eu1Ba2Cu3Oy Crystals

Abstract
The orthorhombic high-T c Eu1Ba2Cu3O y crystals are investigated optically by the polarizing microscope. The crystals are optically anisotropic in the a-b plane, and the phase difference between the advanced- and the retarded-phase axis is 30±3 degrees along the a- and b-axes. According to the reflection formula for metals, the anisotropic conductivity between these two directions is analyzed. The anisotropy of a factor of about 2 is obtained.