Layer-by-layer shuttered molecular-beam epitaxial growth of superconducting Sr1-xLaxCuO2 thin films

Superconducting Sr$_{1-x}$La$_{x}$CuO$_{2}$ thin films have been grown on GdScO$_{3}$ substrates by reflection high-energy electron diffraction calibrated layer-by-layer molecular-beam epitaxy. X-ray diffraction analysis has confirmed the infinite layer structure after an in-situ vacuum annealing step. In-situ photoemission spectroscopy indicates that the
vacuum annealing step employed immediately after film growth to achieve superconducting films results in oxygen loss from the films. The superconducting critical temperature depends on the La content $x$, with the highest value obtained for $x \sim 0.10$. Resistivity as a function of temperature $\rho(T)$ curves of optimally doped samples show a T$^{2}$ temperature dependence characteristic of a scattering process where electron-electron interactions dominate.