Field dependence of the adiabatic temperature change in second order phase transition materials: Application to Gd

The field dependence of the adiabatic temperature change Tad of second order phase transition materials is studied, both theoretically and experimentally. Using scaling laws, it is demonstrated that, at the Curie temperature, the field dependence of Tad is characterized by H1/. Therefore, as the mag...

Descripción completa

Detalles Bibliográficos
Autores: Franco, V., Conde Amiano, Alejandro, Romero-Enrique, J. M., Spichkin, Y. I., Tishin, A. M., Zverev, V. I.
Tipo de recurso: artículo
Fecha de publicación:2009
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/21813
Acceso en línea:http://hdl.handle.net/10261/21813
Access Level:acceso abierto
Palabra clave:Magnetocaloric effects
Curie temperatures
Entropy
Magnetic transitions
Descripción
Sumario:The field dependence of the adiabatic temperature change Tad of second order phase transition materials is studied, both theoretically and experimentally. Using scaling laws, it is demonstrated that, at the Curie temperature, the field dependence of Tad is characterized by H1/. Therefore, as the magnetic entropy change SM follows a H(1−)/ power law, these two dependencies coincide only in the case of a mean field model. A phenomenological construction of a universal curve for Tad is presented, and its theoretical justification is also given. This universal curve can be used to predict the response of materials in different conditions not available in the laboratory (extrapolations in field or temperature), for enhancing the resolution of the data and as a simple screening procedure for the characterization of materials