Anisotropy of High-Temperature Superconductivity in the (100) Plane of YBa2Cu3O7 Film.

A film of high-temperature superconductor (HTSC) YBa2Cu3O7 has been grown on the (100) crystallographic plane of SrLaGaO4 crystal using pulse laser deposition. An X-ray diffraction (XRD) analysis has shown that this film is single-crystal, single-domain, and oriented in the (100) plane. The superconducting transition occurs at 88.8 K and has a width of 1.6 K. Measurements of the temperature dependence of electrical resistance in these films revealed a significant anisotropy of superconductivity in the (100) plane. Due to this specific feature, the critical superconducting-transition temperature, found by measuring the temperature dependence of resistance in the film plane oriented parallel to the CuO planes, exceeded the corresponding value obtained by the same measurement in the direction perpendicular to these planes by 2 K. In addition, it is revealed experimentally that the normal resistance in the former case is smaller than in the latter case by a factor of about 400. [ABSTRACT FROM AUTHOR]