YBa₂Cu₃O_{7 - δ} oriented thin films and magnetically aligned ceramic: Measurement of anisotropic thermopower

We report measurements of the anisotropic thermopower in the normal state of YBa₂Cu₃O_{7 - δ} thin films with three different orientations: a-axis perpendicular to the plane of the substrate; c-axis perpendicular; and coherently tilted on a (305) SrTiO₃ substrate respectively. We have also measured the thermopower of magnetically aligned YBa₂Cu₃O_{7 - δ} ceramic samples. The thermopower in the direction of the c-axis is found to be positive and increases as the temperature increases. The thermopower along the e-axis direction has only a small temperature dependence, while the averaged thermopower in the ab-plane in c-axis films decreases as temperature increases. These results are consistent with those made on single crystals.