Fabrication of polycrystalline La_2NiMnO_6 thin films on LaAlO_3 (100) substrates by chemical solution deposition

摘要

Polycrystalline double-perovskite La_2NiMnO_6 thin films were deposited on LaAlO_3 substrates by chemical solution deposition method and annealed individually in different atmospheres O_2, air and N_2. The X-ray diffraction patterns and Raman scattering spectroscopy reveal that the films annealed in O_2 and air are single phase, while an additional Mn_O_4 phase exists in the films annealed in N_2, which indicates that different annealing atmospheres have great influence on the structure and surface of the films. Moreover, the magnetic properties of the films, including the Curie temperature, coercive field, and remnant magnetization are also strongly dependent on the annealing atmospheres. The optimized films exhibit a Curie temperature of about 280 K, which is close to that of the bulk material.