Orientation-dependent physical properties of layered perovskite La1.3Sr1.7Mn2O7 epitaxial thin films

In this paper, the resistivity and magnetization of orientation-engineered layered perovskite La1.3Sr1.7Mn2O7 epitaxial thin films have been investigated. Epitaxial thin films were deposited on single-crystalline LaAlO3 (LAO) (001), (110) and (111) substrates by pulse laser deposition (PLD) technique. It is found that only the (100)-oriented thin film performs insulator behavior, whereas the (110) and (111)-oriented thin films exhibit obvious metal-insulator transition at 70 K and between 85 and 120 K, respectively. Moreover, the same spin freezing temperature and different spin-glass-like transition temperatures have been observed in various oriented films. The observed experimental results were discussed according to the electron-transport mechanism and spin dynamics.