Magnetocaloric effect in a La0.7Ca0.3MnO3 single crystal

A large entropy change in a single crystal of La0.7Ca0.3MnO3, which undergoes a first-order ferromagnetic to paramagnetic transition at 227 K, was observed. As a result of a sharp drop in magnetization associated with ferromagnetic-paramagnetic transition, the magnetic entropy change, DeltaS(M), reaches a maximum value of about 6.42 J/kg K for an applied field of 5 T. The DeltaS(M) distribution here is much more uniform than that of pure Gd metal, which is desirable for an Ericson-cycle magnetic refrigerator. Through these results, the La0.7Ca0.3MnO3 single crystal is strongly recommended to use as an active magnetic refrigerant for magnetic refrigerators. (C) 2002 Elsevier Science B.V. All rights reserved.