Percolation processes and spin-reorientation of PrNi5-xCox

• Tipo: Artigo em Revista Científica Internacional
• Data: 2009

Autores

rocco, d. l. (Autor) Outra; amaral, j. s. (Autor) Outra; leitao, j. v. (Autor) Outra; amaral, v. s. (Autor) Outra; reis, m. s. (Autor) Outra; fernandes, r. p. (Autor) Outra; pereira, a. m. (Autor) Outra; araujo, j. p. (Autor) FCUP; martins, nuno v. (Autor) Outra; tavares, p. b. (Autor) Outra; coelho, a. a. (Autor) Outra

Revista

Título: Physical Review B - Condensed Matter and Materials Physics

Vol. 79

ISSN: 1098-0121

Editora: American Physical Society

Indexação

ISI Web of Knowledge - 16 Citações

Scopus - 16 Citações

Outras Informações

ID Authenticus: P-003-RN6

DOI: 10.1103/physrevb.79.014428

Abstract (EN): In the present work we report on the structural and magnetic behaviors of the PrNi5-xCox intermetallic compounds. Due to the competition between the anisotropy energies of both Co and Pr sublattices, this series has a spin-reorientation phenomenon at low temperature (140 K). The Curie temperature, as a function of Co content, has a sudden increase above a critical concentration x(c)similar to 1.9 and this feature is assigned as a percolation of geometrically spaced Co clusters. This assumption is explained based on the critical exponent of percolation theory. The series presents therefore a rich magnetic phase diagram, which could be established over a full doping range, i.e., from x=0 to x=5. We have also studied these compounds on the magnetocaloric point of view and found a quite large full width at half maximum (delta T-FWHM) of the magnetic entropy change curves for some of the compositions, due to the merging of the Delta S peaks associated with the spin-reorientation process and the Curie temperature T-C. In addition, the series has an appreciable relative cooling power, which is therefore suitable to be used in a magnetic refrigerator operating in a large range of temperature.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6