Artículos de revistas
Heat Flux Measurements Of Tb3m Series (m = Co, Rh And Ru): Specific Heat And Magnetocaloric Properties
Registro en:
Physica B: Condensed Matter. Elsevier Science Bv, v. 503, p. 64 - 69, 2016.
0921-4526
1873-2135
WOS:000386818900011
10.1016/j.physb.2016.09.007
Autor
Monteiro
J. C. B.; Lombardi
G. A.; dos Reis
R. D.; Freitas
H. E.; Cardoso
L. P.; Mansanares
A. M.; Gandra
F. G.
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) We report on the magnetic properties and magnetocaloric effect (MCE) for the Tb3M series, with M = Co, Rh and Ru, obtained using a heat flux technique. The specific heat of Tb3Co and Tb3Rh are very similar, with a first order type transition occurring around 6 K below the magnetic ordering temperature without any corresponding feature on the magnetization. The slightly enhanced electronic specific heat, the Debye temperature around 150 K and the presence of the magnetic specific heat well above the ordering temperature are also characteristic of many other compounds of the R3M family (R = Rare Earth). The specific heat for Tb3Ru, however, presents two peaks at 37 K and 74 K. The magnetization shows that below the first peak the system presents an antiferromagnetic behavior and is paramagnetic above 74 K. We obtained a magnetocaloric effect for M= Co and Rh, -Delta S=12 J/kg K, but for Tb3Ru it is less than 3 J/kg K (mu(0)Delta H = 5 T). We believe that the experimental results show that the MCE is directly related with the process of hybridization of the (R)5d-(M)d electrons that occurs in the R3M materials. (C) 2016 Elsevier B.V. All rights reserved. 503 64 69 FAPESP FAEPEX-Unicamp CNPq CAPES Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)