The magnetization of epitaxial nanometric CoFe2O4(001) layers

• Autor(a) principal: Rigato, Franco
• Data de Publicação: 2009
• Outros Autores: Geshev, Julian Penkov, Skumryev, Vassil, Fontcuberta Griño, Josep
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/96122
• topic: Física da matéria condensada; Anisotropia magnética; Propriedades magnéticas; Camadas epitaxiais magnéticas; Materiais nanoestruturados; Compostos de cobalto; Ferritas

We have studied the magnetic anisotropy of nanometric CoFe2O4 (CFO) thin films grown on (100) SrTiO3 (STO) substrates. It has been found that epitaxial substrate-induced compressive strain makes the normal-to-film axis harder than the in-plane directions. In agreement with some previous reports, the magnetization loops are found to display a characteristic shrinking at low fields. Detailed structural and microstructural analyses, together with a modeling of the magnetization loops, revealed that the microstructure of the films, namely, the coexistence of a continuous CFO and a distribution of pyramidal CFO huts emerging from the surface, are responsible for this peculiar feature. We argue that this behavior, which significantly impacts the magnetic properties, could be a general trend of spinel films grow on (001) STO substrates.