Measurements of heat capacity associated with the magnetic transition in La_0.7A_0.3MnO3 (A = Ca, Sr, Ba)
Abstract
It is well known that the transition temperature of the paramagnetic insulator-magnetic metal transition in the perovskite manganites La_1-xA_xMnO3 (x = 0.3, A = divalent metal) depends sensitively on the average size of A-site cations. In order to elucidate the physical reason for this behavior, we have carried out high-resolution measurements of heat capacity of samples with A = Ca, Sr, Ba. By critically comparing these results as well as magnetization measurements, we were able to draw a conclusion: as the average size of the A-site cation gets smaller than a certain value, the two-phase coexistence sets in and the transition temperature abruptly decreases.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2001
- Bibcode:
- 2001APS..MARS24010J