M. Balasoiu, S. G. Barsov, D. Bica, L. Vekas, S. I. Vorob'ev, K. I. Gritsaj, V. N. Duginov, V. A. Zhukov, E. N. Komarov, V. P. Koptev, S. A. Kotov, T. N. Mamedov, C. Petrescu, G. V. Shcherbakov, “μSR study of the properties of Fe3O4-based nanostructured magnetic systems”, Pis'ma v Zh. Èksper. Teoret. Fiz., 2008, Volume 88, Issue 3,Pages 243

This article is cited in 6 papers

CONDENSED MATTER

μSR study of the properties of Fe₃O₄-based nanostructured magnetic systems

M. Balasoiu^ab, S. G. Barsov^c, D. Bica^d, L. Vekas^d, S. I. Vorob'ev^c, K. I. Gritsaj^a, V. N. Duginov^a, V. A. Zhukov^a, E. N. Komarov^c, V. P. Koptev^c, S. A. Kotov^c, T. N. Mamedov^a, C. Petrescu^e, G. V. Shcherbakov^c

^a Joint Institute for Nuclear Research, Dubna, Moscow region, 141980, Russia
^b Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, 76900, Romania
^c Petersburg Nuclear Physics Institute, Russian Academy of Sciences, Gatchina, Leningrad region, 188300, Russia
^d Center for Fundamental and Advanced Technical Research, Timisoara, 300223, Romania
^e R\&D Institute for Electrotechnics, 74204 Bucharest, Romania

Abstract: A ferrofluid based on Fe₃O₄ nanoparticles dispersed in heavy water D₂O is studied using the μSR method. The experiment has been carried out at temperatures 26–300 K. It is found that the diamagnetic (muon) fraction is formed in the ferrofluid in about the same amount as in D₂O, but the muon-spin relaxation rate in the ferrofluid is much higher than in D₂O. A significant shift of the muon-spin precession frequency in the ferrofluid is observed. It is shown that the shift of the muon precession frequency as a function of the external magnetic field is described by the Langevin function typical of paramagnetic magnetization. The mean magnetic field in the medium due to magnetic-nanoparticle polarization in an external field is experimentally determined. The nanoparticle sizes are estimated.

PACS: 75.20.-g, 75.50.Mm, 75.75.+a, 76.75.+i

Received: 26.06.2008
Revised: 02.07.2008