Understanding the influence of the first-order magnetic phase transition on the magnetocaloric effect: application to Gd5(SixGe1−x)4

Instituto de Fı́sica-Electronica Quantica, Universidade do Estado do Rio de Janeiro, IF, DEQ, Rua São Francisco Xavier, 524, 20550013 Rio de Janerio, Brazil; Instituto de Fı́sica ‘Gleb Wataghin’, Universidade Estadual de Campinas UNICAMP, C.P. 6165, Campinas 13 083 970, SP, Brazil
Journal of Magnetism and Magnetic Materials (Impact Factor: 2). 01/2004; DOI: 10.1016/j.jmmm.2003.10.013

ABSTRACT In this article, we investigate the influence of the first-order ferromagnetic–paramagnetic phase transition, on the magnetocaloric effect, under the combined effect of external magnetic field, pressure and magnetoelastic deformation. An application is made to Gd5(SixGe1−x)4, for x=0.43 and 0.5. The obtained result leads to a good theoretical adjustment of the experimental data for isothermal magnetic entropy change.

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