Nonlinear response of superparamagnets with finite damping:: An analytical approach -: art. no. 064415

被引：16

作者：

García-Palacios, JL

Garanin, DA

机构：

[1] Univ Zaragoza, CSIC, Dept Fis Mat Condensada, E-50009 Zaragoza, Spain

[2] Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, E-50009 Zaragoza, Spain

[3] Uppsala Univ, Dept Mat Sci, SE-75121 Uppsala, Sweden

[4] Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany

来源：

PHYSICAL REVIEW B | 2004年 / 70卷 / 06期

关键词：

D O I：

10.1103/PhysRevB.70.064415

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The strongly damping-dependent nonlinear dynamical response of classical superparamagnets is investigated by means of an analytical approach. Using rigorous balance equations for the spin occupation numbers a simple approximate expression is derived for the nonlinear susceptibility. The results are in good agreement with those obtained from the exact (continued-fraction) solution of the Fokker-Planck equation. The formula obtained could be of assistance in the modeling of the experimental data and the determination of the damping coefficient in superparamagnets.

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页码：064415 / 1

页数：7

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