• Bonilla, C.M.; Bartolomé, F.; García, L.M.; Parra-Borderías, M.; Herrero-Albillos, J.; Franco, V.: A new criterion to distinguish the order of magnetic transitions by means of magnetic measurements. Journal of Applied Physics 107 (2010), p. 09E131/1-3

10.1063/1.3366614

Abstract:
A universal curve for the magnetic entropy change has been found to exist for a variety of materials with second order phase transitions. We have studied whether this universal behavior of the magnetocaloric effect is maintained in materials with first order phase transition, including RCo2 Laves phases and mixed La2/3(CaxSr1−x)1/3MnO3 manganites, which present both second order and first order magnetic ordering phase transitions. The rescaled magnetic entropy change curves for different applied fields collapse onto a single curve only for materials with second order phase transition. This universal curve may be used as a criterion for determining the order of magnetic phase transitions from purely magnetic measurements.