Artículos de revistas
Photothermally modulated magnetic resonance applied to the study of the magnetic phase transition in gadolinium thin films
Registro en:
Thin Solid Films. Elsevier Science Sa, v. 520, n. 9, n. 3634, n. 3640, 2012.
0040-6090
WOS:000301627100037
10.1016/j.tsf.2011.12.042
Autor
Soffner, ME
Tedesco, JCG
Pedrochi, F
Gadioli, GZ
de Moraes, MAB
Guimaraes, AO
da Silva, EC
Mansanares, AM
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 explore the photothermally modulated magnetic resonance technique to investigate gadolinium thin films deposited on fused quartz substrate, as a function of thickness and thermal treatment, around the magnetic phase transition temperature. It has been observed that the maximum amplitude of the photothermally modulated magnetic resonance (PM-MR) signal takes place near the phase transition temperature, similarly to the magnetocaloric effect, for which Gd has been the prototype material. The reason is that both depend on the temperature derivative of the magnetization, which maximizes at the phase transition. Besides, there is a narrowing of transition with thermal treatment, confirming that thermal treatment stabilizes the film structure. For frequency scan measurements, the heat diffusion in a two-layer system was considered, and a depth profile study was carried out in order to investigate heterogeneities along the film thickness. From the PM-MR response as a function of the modulation frequency it was possible to estimate the thermal properties of the Gd film. Magnetization, X-ray and electron spin resonance measurements were used to complement the analysis and support the conclusions. (c) 2011 Elsevier B.V. All rights reserved. 520 9 3634 3640 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) FAEPEX-Unicamp 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)