| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09090400 Santo Andre, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | JOURNAL OF PHYSICS-CONDENSED MATTER; v. 23, n. 22 JUN 8 2011. |
| Web of Science Citations: | 3 |
| Abstract | |
A scaling behavior between heat capacity C(P){*} and thermal expansion coefficient times temperature Omega T lambda, where. is a scale factor, is obtained for ferromagnetic La(1-x)Ca(x)MnO(3) with x = 0.20, 0.25, 0.30, 0.34, 0.40, and 0.45 compounds. The pressure derivative of the magnetic phase transition temperature obtained through a scaling method is in good agreement with experimental results for all samples. The critical exponents associated with the specific heat (alpha) for x = 0.25, 0.30, and 0.34 are very close to the phase boundary where continuous phase transitions become discontinuous. This is attributed to strong coupling among the spin, charge, and lattice degrees of freedom, which indicates that the magnetization alone would be a poor choice for the order parameter in these systems. Based on thermodynamic arguments, a phase diagram with diverging, cusp-like, near first order, and first order phase transitions is presented. (AU) | |
| FAPESP's process: | 09/18618-5 - Synthesis and characterization of thermodynamic and electrical transport properties of advanced materials |
| Grantee: | José Antonio Souza |
| Support Opportunities: | Regular Research Grants |