Determination of the blocking temperature of magnetic nanoparticles: The good, the bad, and the ugly

A numerically solved two-level Stoner-Wohlfarth model with thermal agitation is used to simulate Zero Field Cooling (ZFC)-Field Cooling (FC) curves of monosize and polysize samples and to determine the best method for obtaining a representative blocking temperature TB value of polysize samples. The...

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Detalhes bibliográficos
Autores: Bruvera, Ignacio Javier, Mendoza Zélis, Pedro, Calatayud, M. P., Goya, G. F., Sanchez, Francisco Homero
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2015
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/142870
Acesso em linha:http://hdl.handle.net/11336/142870
Access Level:Acceso aberto
Palavra-chave:Blocking temperature
Magnetic anisotropy
Nanoparticles
ZFC-FC
https://purl.org/becyt/ford/2.10
https://purl.org/becyt/ford/2
Descrição
Resumo:A numerically solved two-level Stoner-Wohlfarth model with thermal agitation is used to simulate Zero Field Cooling (ZFC)-Field Cooling (FC) curves of monosize and polysize samples and to determine the best method for obtaining a representative blocking temperature TB value of polysize samples. The results confirm a technique based on the T derivative of the difference between ZFC and FC curves proposed by Micha et al. (the good) and demonstrate its relation with two alternative methods: the ZFC maximum (the bad) and the inflection point (the ugly). The derivative method is then applied to experimental data, obtaining the TB distribution of a polysize Fe3O4 nanoparticle sample suspended in hexane with an excellent agreement with TEM characterization.