Magnetic relaxation measurements of (alpha)-Fe2O3 antiferromagnetic particles below 1 K

In this paper we report magnetic relaxation data for antiferromagnetic a-Fe2O3 particles of 5-nm mean diameter in the temperature range 0.1–25 K. The average spin value of these particles S.124 and the uniaxial anisotropy constant D.1.631022 K have been estimated from the experimental values of the...

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Detalles Bibliográficos
Autores: Barco, Enrique del, 1968-, Durán, M., Hernández Ferràs, Joan Manel, Tejada Palacios, Javier, Zysler, R. D., Vásquez Mansilla, M., Fiorani, D.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/10874
Acceso en línea:https://hdl.handle.net/2445/10874
Access Level:acceso abierto
Palabra clave:Relaxació magnètica
Propietats magnètiques
Magnetic properties
Magnetic relaxation
Descripción
Sumario:In this paper we report magnetic relaxation data for antiferromagnetic a-Fe2O3 particles of 5-nm mean diameter in the temperature range 0.1–25 K. The average spin value of these particles S.124 and the uniaxial anisotropy constant D.1.631022 K have been estimated from the experimental values of the blocking temperature and anisotropy field. The observed plateau in the magnetic viscosity from 3 K down to 100 mK agrees with the occurrence of spin tunneling from the ground state SZ5S. However, the scaling M vs T ln(n0t) is broken below 5 K, suggesting the occurrence of tunneling from excited states below this temperature.