Enhancement of magnetoresistance and magnetocaloric effect at room temperature in polycrystalline Pr 0.8 - x La x Sr 0.2 MnO 3 (x = 0.2) compound

The effect of chemical pressure on the ferromagnetic insulator ground state and its effect on magnetotransport and magnetocaloric properties has been explored in this study. Magnetic and magnetotransport measurements reveal that the increased chemical pressure in ${\mathrm{Pr}}_{0.6}{\mathrm{La}}_{0.2}{\mathrm{Sr}}_{0.2}{\mathrm{MnO}}_3$ due to the partial substitution by La in ${\mathrm{Pr}}_{0.8}{\mathrm{Sr}}_{0.2}{\mathrm{MnO}}_3$ compound change the low-temperature insulator phase to the metallic phase. A room temperature enhancement of magnetoresistance (MR), as well as large relative cooling power (RCP), have been achieved with increasing chemical pressure in x = 0.2 compound. This enhancement of MR and magnetocaloric effect (MCE) in ${\mathrm{Pr}}_{0.6}{\mathrm{La}}_{0.2}{\mathrm{Sr}}_{0.2}{\mathrm{MnO}}_3$ compound have been attributed to the short- range ferromagnetic cluster formation at higher temperature $(T>T_C)$.