Role of the Dipolar Interaction on the Macroscopic State of Magnetic Nanoparticle Systems: A Monte Carlo Study

被引：6

作者：

Baldomir, D. ^{[1
,2
]}

Serantes, D. ^{[1
,2
]}

Pereiro, M. ^{[1
,2
]}

Botana, J. ^{[1
,2
]}

Arias, J. E. ^{[1
]}

Masunaga, S. H. ^{[2
]}

Rivas, J. ^{[2
]}

机构：

[1] Univ Santiago de Compostela, Inst Invest Tecnolox, E-15782 Santiago De Compostela, Galiza, Spain

[2] Univ Santiago de Compostela, Dept Fis Aplicada, E-15782 Santiago De Compostela, Galiza, Spain

来源：

JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY | 2010年 / 10卷 / 04期

关键词：

Magnetic Nanoparticles; Monte Carlo Simulation; Magnetic Dipolar Interaction; ANISOTROPY;

D O I：

10.1166/jnn.2010.1439

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

We have performed Monte Carlo simulations to treat the effect of the dipolar interaction in assemblies of superparamagnetic nanoparticles. Our simulations reproduce correctly the increase of the blocking temperature (T-B) as the concentration increases, as observed experimentally. Interestingly, we have observed a progressive displacement of the M-2 versus H/M isotherms (Arrott plots) from the origin as the concentration of nanoparticles increases. Moreover, the curvature of the isotherms at T > T-B changes from positive to negative slope at high sample concentrations, resembling the shape of a first order phase transition. These results are surprisingly similar to that found in a conventional magnetic phase transition under the effect of a random anisotropy or a random field.

引用

页码：2717 / 2721

页数：5

共 17 条

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[2]

Allen M. P., 1987, COMPUTER SIMULATION

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