Structural transition induced enhancement of magnetization and magnetoresistance in epitaxial (Pr0.5Ba0.5MnO3)1−x:(CeO2)x vertically aligned thin films†
Epitaxial (Pr0.5Ba0.5MnO3)1−x:(CeO2)x (PBMO:CeO2, x = 0, 10%, 20%, 35%, and 50% stands for the molar ratio of the CeO2 secondary phase) vertically aligned nanocomposite (VAN) thin films were successfully fabricated on single crystalline (001) (La,Sr)(Al,Ta)O3 substrates by pulsed laser deposition. With increasing x, a structural transition induced by the vertical strain from the CeO2 secondary phase was observed at 20% ≤ x ≤ 35% by reciprocal space mapping. What's more, it is not only the enhancement of magnetoresistance that was observed but also the increasing magnetization. The maximum magnetization and magnetoresistance were achieved at x = 35%, which are almost 4.7 times (at 20 K) and 1.6 times (at 110 K) as high as those at x = 0%, respectively. Such great enhancement of magnetization can be attributed to the vertical strain induced structural transition. Our research indicates that the structural transition induced by the introduction of secondary phase CeO2 plays an important role in improving the magnetic and transport properties of VAN thin films.