Enhanced magnetic viscosity at low temperatures in [Fe/Cr(0 0 1)] 10 multilayers

• Published in: Journal of magnetism and magnetic materials 2007-09, Vol.316 (2), p.344-347
• Main Authors: Aliev, F.G., Guerrero, R., Pryadun, V., Villar, R., Cebollada, A., Anguita, J., Schad, R., Vavra, I.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Fe thin film; Interfacial magnetic properties (multilayers, magnetic quantum wells, superlattices, magnetic heterostructures); Magnetic nanostructure; Magnetic properties and materials; Magnetic properties of surface, thin films and multilayers; Physics; Relaxation effect
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2007.03.037

We report on magnetic aftereffect measurements in strongly and weakly antiferromagnetically (AFM)-coupled epitaxial [Fe/Cr(1 0 0)] 10 and in epitaxial Fe(1 0 0), near the orientation transition (OT) between the easy and hard axes, studied at time scales up to 10 3 s and between 300 and 1.8 K. In strongly coupled multilayers, the relaxation is nearly logarithmic in time, has an intrinsic character, and the maximum relaxation rate is almost temperature independent down to 10 K and strongly increases below 10 K. The magnetic relaxation in Fe(0 0 1) films was, however, much faster at T > 10 K, but at lower temperatures it is nearly blocked making possible the observation of magnetization jumps of Barkhausen type. The unusual magnetic aftereffect in the Fe/Cr multilayers could be due to opening of relaxation channels through the Cr that separates the Fe layers.