Large positive magnetocaloric effect in a perovskite manganite

Mahendiran, R.; Ueland, B. G.; Schiffer, P.; Maignan, A.; Martin, C.; Hervieu, M.; Raveau, B.; Ibarra, M. R.; Morellon, L.

Large positive magnetocaloric effect in a perovskite manganite

Authors

Description

We investigate the magnetothermodynamic properties of the perovskite manganite Pr0.46Sr0.54MnO3. Our data imply that the paramagnetic to antiferromagnetic transition at TN = 210 K is first order with an abrupt decrease of volume (~ 0.14 % in zero magnetic field) and is accompanied by a sharp anomaly in specific heat. Upon application of a sufficiently large magnetic field, the antiferromagnetic phase transforms into a ferromagnetic phase with a sharp increase in sample volume. This field induced transition results in a large positive magnetocaloric effect just below TN (∆Sm = 10.4 Jkg-1K-1 at H = 5.5 T), which is associated with the increasing stability of the antiferromagnetic state with decreasing temperature.
16 pages nad 5 figures