The Magnetic Properties and Magnetocaloric Effect of Pr_0.7Sr_0.3MnO₃ Thin Film Grown on SrTiO₃ Substrate

The magnetic behaviors and magnetocaloric effect (MCE) of Pr_0.7Sr_0.3MnO₃ (PSMO-7) film grown on a (001) SrTiO₃ single-crystal substrate by a pulsed laser deposition (PLD) were studied in this paper. X-ray diffraction with a high resolution (HRXRD) measurement shows that PSMO-7 film is grown with a (001) single orientation. The magnetic properties and the MCE related to the ferromagnetic (FM) phase transition of the PSMO-7 film are investigated using the temperature dependence of magnetization M(T) and the magnetic field dependence of magnetization M(H). The M(T) data suggest that with decreasing temperatures, the PSMO-7 film goes through the transition from the paramagnetic (PM) state to the FM state at around the Curie temperature (T_C). The T_C (about 193 K) can be obtained by the linear fit of the Curie law. Magnetic hysteresis loop measurements show that the PSMO-7 film exhibits the FM feature at temperatures of 10, 100, and 150 K (low magnetic hysteresis can be found), while the film reveals the PM feature with the temperature increased up to 200 and/or 300 K. The research results of M(H) data are consistent with the M(T) data. Furthermore, the magnetic entropy change (-ΔSM) of the PSMO-7 film was studied. It was found that the maximum value of (-ΔSM) near T_C reaches about 4.7 J/kg·K under the applied field change of 20 kOe, which is comparable to that of metal Gd (-ΔSM of 2.8 J/kg K under 10 kOe), indicating the potential applications of PSMO-7 film in the field of magnetic refrigeration.