The effect of stress on the magnetic properties of sol–gel-derived Pr_0.9Ca_0.1MnO₃ thin films

The Pr_0.9Ca_0.1MnO₃ (PCMO) thin films prepared by sol–gel method suffered tensile and compressive stress grown on SrTiO₃ and LaAlO₃ substrates. The hysteresis loops at different temperatures show that the coercivity field with tensile stress is larger and the pinning potential of ferromagnetism motion is much stronger. The temperature dependence of the ZFC and FC magnetizations indicates that the stress significantly affects the ferromagnetic (FM) and antiferromagnetic transition temperature of PCMO, and the Curie temperature (T_C) decreases with tensile stress. The films show strong anisotropy properties that the magnetization increases much faster with the magnetic field when H⊥c, but the coercive field and saturation magnetization do not change significantly. In addition, the persistent photoinduced magnetization is investigated, and significant improvement of the FM ordering was observed in low temperature. And the saturation magnetization of each Mn ion is significantly affected by orientation and illumination.