Suppression of Precipitates in the La2-xSrxCuO4 Films Grown on LaSrAlO4 Substrates by Introducing Homoepitaxial Layer

Abstract

We have investigated impacts of a LaSrAlO4 (LSAO) homoepitaxial layer (HL) on the quality of La2-xSrxCuO4 (LSCO) films grown on single crystal LSAO (001) substrates by pulsed laser deposition. Introduction of the LSAO HL significantly suppressed the segregation of impurity phases in the LSCO films especially in a higher Sr-doping range (x > 0.20), leading to the improvement of the surface morphology. The suppression of impurity phases also enables us to obtain the desired stoichiometry of the LSCO films, which show the superconducting dome in the x-temperature phase diagram very similar to that of bulk samples.