Effect of simultaneous application of magnetic field and pressure on magnetic transitions in La_0.5Ca_0.5MnO₃

Abstract

We study combined effect of hydrostatic pressure and magnetic field on the magnetization of La_0.5Ca_0.5MnO₃. We do not observe any significant effect of pressure on the paramagnetic to ferromagnetic transition. However, pressure asymmetrically affects the thermal hysteresis across the ferromagnetic-antiferromagnetic first-order transition, which has strong field dependence. Though the supercooling (T^∗∗) and superheating (T^{∗ ∗}) temperatures decrease and the value of magnetization at 5 K (M_{5 K}) increases with pressure, T^∗ and M_{5 K} shows abrupt changes in tiny pressure of 0.68 kbar. These anomalies enhance with field. In 7 T field, transition to antiferromagnetic phase disappears in 0.68 kbar and M_{5 K} show significant increase. Thereafter, increase in pressure up to ~10 kbar has no noticeable effect on the magnetization.