Magnetic-field-dependent morphology of self-organized Fe on stepped Si(111) surfaces

The present work reports on Fe thin films grown on vicinal Si(111) substrates via rf magnetron sputtering. The dependencies of the growth mode and magnetic properties of the obtained iron nanostructures on both crystallographic surface orientation and on the direction of the very weak stray magnetic...

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Detalles Bibliográficos
Autores: Santos, Mauricio Cougo dos, Geshev, Julian Penkov, Pereira, Luis Gustavo, Schmidt, Joao Edgar
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Brasil
Institución:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositorio:Repositório Institucional da UFRGS
Idioma:inglés
OAI Identifier:oai:www.lume.ufrgs.br:10183/96126
Acceso en línea:http://hdl.handle.net/10183/96126
Access Level:acceso abierto
Palabra clave:Magnetismo
Materiais nanoestruturados
Filmes finos magneticos
Forca coerciva
Histerese magnética
Reversão de magnetização
Microscopia de tunelamento
Descripción
Sumario:The present work reports on Fe thin films grown on vicinal Si(111) substrates via rf magnetron sputtering. The dependencies of the growth mode and magnetic properties of the obtained iron nanostructures on both crystallographic surface orientation and on the direction of the very weak stray magnetic field from the magnetron gun were studied. Scanning tunneling microscopy images showed strong dependence of the Fe grains’ orientation on the stray field direction in relation to the substrate’s steps demonstrating that, under appropriately directed magnetic field, Si surfaces can be used as templates for well-defined self-assembled iron nanostructures. Magneto-optical Kerr effect hysteresis loops showed an easy-axis coercivity almost one order of magnitude smaller for the film deposited with stray field applied along the steps, accompanied with a change in the magnetization reversal mode. Phenomenological models involving coherent rotation and/or domain-wall unpinning were used for the interpretation of these results.