Strain Effect of $a$ -Axis-Oriented Sr1−xLaxCuO2 Thin Films Grown on LaAlO3 Substrates.

The epitaxial thin films of electron-doped infinite-layer cuprate superconductor Sr1-xLaxCuO2 (SLCO; $x = 0.1$ ) were grown by dc magnetron sputtering, and their structural and electrical properties were systematically investigated by changing mismatch to substrate and SLCO film thickness, with a reduction annealing period under vacuum to remove the excess apex oxygen. Thin films of BaySr1−yTiO3 (BSTO) with y = 0.55$ , 0.6, and 0.7, prepared on (001) (La0.18Sr0.82)(Al0.59Ta0.41)O3 substrates, were used as the epitaxial buffer layers to induce different levels of tensile strain in c$ -axis-oriented SLCO, while (001) LaAlO3 substrates were used for the growth of a value of c$ -axis oriented SLCO was obtained on the BSTO ( y = 0.6$ ) layers and the mismatch dependence of strain relaxation thickness was clarified. The strain in a was obtained in the $a$ -axis SLCO for the first time. Based on these results, the strain effects of the SLCO film properties are discussed. [ABSTRACT FROM AUTHOR]