Role of Dipolar Interactions and Volume Particle Size Distribution on the Nonmonotonic Magnetic Field Dependence of the Blocking Temperature in Magnetic Nanoparticles

Author(s)

Masunaga, Sueli H. ^[1] ; Jardim, Renato F. ^[1] ; Correia, Marcos J. ^[2] ; Figueiredo, Wagner ^[2]

Affiliation

^[1] Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, SP - Brazil

^[2] Univ Fed Santa Catarina, Dept Fis, BR-88040900 Florianopolis, SC - Brazil

• Document type: Journal article
• Source: Journal of Physical Chemistry C; v. 120, n. 1, p. 765-770, JAN 14 2016.
• Web of Science Citations: 3

Abstract

The nonmonotonic behavior of the magnetic field dependence H of the superparamagnetic blocking temperature T-B(H) (or T-max(H)) of an assembly of magnetic nanoparticles NPs was studied both experimentally and theoretically. We have combined the measurements of zero-field cooling ZFC magnetization curves under H performed on samples with increasing concentration of Ni nanoparticles and Monte Carlo simulations. As a result, we have found that increasing the strength of the dipolar interaction between granules and the occurrence of a very narrow width of a log-normal volume particle size distribution of the NPs suppress the nonmonotonic behavior of T-max(H). (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 14/19245-6 - Search for novel superconducting materials
• Grantee: Renato de Figueiredo Jardim
• Support type: Scholarships abroad - Research