Epitaxial thin films of electron-doped infinite-layer (IL) cuprate superconductor Sr1-xLaxCuO 2 (SLCO, x = 0.1) were grown by dc magnetron sputtering, and their structural and electrical properties were investigated systematically by changing the reduction annealing period under vacuum to remove excess apical-oxygen and the SLCO film thickness. Thin films of BaySr1-yTiO3 with y = 0.4, 0.55, and 0.7, prepared on (001) (La0.18Sr0.82)(Al0.59Ta0.41)O3 (LSAT) substrates, were used as epitaxial buffer layers to induce different types of strain in SLCO. For the tensile strained SLCO films on Ba0.55Sr0.45TiO3 and on Ba0.7Sr0.3TiO3 layers, short time (several minutes) reduction annealing was found to be effective for the removal of excess apical-oxygen and the appearance of superconductivity, whereas the reduction annealing was less effective for the compressively strained SLCO films on Ba 0.4Sr0.6TiO3 layers. Moreover, strong thickness dependences of superconducting properties have been observed for tensile strained SLCO films on Ba0.55Sr0.45TiO3 and on Ba0.7Sr0.3TiO3 layers. Based on these results, the strain and reduction effects of the SLCO film properties are discussed.
- Infinite-layer compound
- strain effect
- superconducting thin films
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering