A COMPARATIVE REVIEW OF THE THICKNESS-DEPENDENT SUPERCONDUCTING PROPERTIES OF YBA₂CU₃O₇−Δ THIN FILMS

Abstract

This paper presents a comparative analysis of the thickness dependence of the superconducting transition temperature (TcT_cTc​) in YBa₂Cu₃O₇−δ (YBCO) thin films based on previously published studies. The effects of film thickness, substrate type, and growth conditions on the superconducting properties are systematically reviewed. The comparison shows that TcT_cTc​ generally decreases as the film thickness is reduced to the nanoscale due to the combined influence of epitaxial strain, oxygen deficiency, finite-size effects, and surface/interface scattering. Differences observed among films grown on STO, LAO, LaO, and PrBCO-based heterostructures demonstrate the significant role of substrate-induced lattice mismatch and structural quality. The results indicate that optimizing film thickness together with substrate selection and oxygenation conditions is essential for achieving high superconducting performance. This review provides a comprehensive understanding of thickness-dependent superconductivity in YBCO thin films and highlights its importance for superconducting nanoelectronics, quantum devices, and high-field magnet applications.