Effect of hydrostatic pressure on magnetic and magnetocaloric properties in La0.35Pr0.35Ca0.3MnO3

Abstract

Magnetization of polycrystalline La0.35Pr0.35Ca0.3MnO3 sample has been measured as a function of temperature (T) and magnetic field (H) under various external hydrostatic pressures (P) up to ~1GPa. At ambient P, the sample exhibits paramagnetic (PM)–ferromagnetic (FM) transition (TC) at 167K and 173K in cooling and warming cycles respectively under the magnetic field (µ0.H) of 0.1T. It also shows a hysteresis during both temperature- and field- dependence of magnetization measurements at ambient P, suggests the presence of a first-order transition. Moreover, the field dependence of magnetization shows S type field-induced metamagnetic transition (FIMMT) over a temperature range below TC in the FM state. The application of P in M(T) increases TC at a rate [dTC/dP] of 13.9K/GPa, but the thermally-driven first-order transition is not affected by P. However, the applied P suppresses FIMMT and reduces field-driven first-order transition in the magnetization isotherms [M(H)]below TC. H increases both magnetic entropy change (∆Sm) and Relative Cooling Power (RCP), whereas the P slightly increases ∆Smmax and no appreciable change in RCP. These results suggest that H and P can be used as a tool to enhance magnetocaloric values in the phase separated manganites.