Phase separation and magnetocaloric effect in Pr0.5−xGdx Sr0.5MnO3 system

• Gd doping in Pr0.5−xGdxSr0.5MnO3 (with x = 0, 0.05 and 0.1) enhances the antiferromagnetic interactions.
• The studied samples are characterized by the phase separation phenomenon.
• Magnetic properties are in agreement with electrical results.

The magnetic properties and the magnetocaloric effect have been studied in Pr0.5−xGdxSr0.5MnO3 (x = 0, 0.05 and 0.1) manganites prepared by the solid state reaction method. Magnetic measurements versus temperature in an applied magnetic field of 0.05 T show that the all samples exhibit a paramagnetic to ferromagnetic transition when temperature decreases. The x = 0.1 sample shows a clear transition, from the ferromagnetic state to the antiferromagnetic one at TN = 125 K. The Curie temperature decreases gradually with increasing gadolinium content. The absolute values of the maximum of magnetic entropy change |ΔSM| for an applied magnetic field of 2 T are equal to1.26, 1.25 and 1.02 J kg−1 K−1 for x = 0, 0.05 and 0.1, respectively. The decrease of |ΔSM| with Gd doping can be attributed to the enhancement of phase separation phenomenon. The magnetic entropy curves follow the universal law corresponding to the second-ordered paramagnetic-ferromagnetic transition.