Heat capacity and magnetization measurement of phase-separated Pr_0.65(Ca_0.75Sr_0.25)_0.35MnO3 single crystal
Abstract
Perovskite manganites are known to include in their rich phase diagrams sharp, metamagnetic transitions at low temperatures from antiferromagnetic charge-orbital ordered insulators to ferromagnetic metals. We measured the heat capacity C and magnetization M of such a phase-separated Pr_0.65(Ca_0.75Sr_0.25)_0.35MnO3 single crystal as a function of temperature T and magnetic field H. The magnetic state of the crystal is dependent on the field and cooling history. A field-induced, step-like transition in M is observed at low T (< 10 K) at a critical field of 1.65 T. A discontinuous transition occurs at approximately the same field in the C(H) data at the same T indicating that the metamagnetic transition in M(H) is related to the thermodynamic transition in C(H). This abrupt, field-induced state in M and C persists up to ∼ 100 K although the field where the transition occurs and the stiffness of the transition change as T increases. We also measured C(T) at low temperatures both below (H = 0 T) and above (H = 2 T) the critical field ( ∼ 1.65 T) to investigate the characteristics of the transition and two different phases.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARJ24002G