Temperature-dependent magnetic properties of FePt: Effective spin Hamiltonian model

被引：223

作者：

Mryasov, ON ^{[1
]}

Nowak, U ^{[1
]}

Guslienko, KY ^{[1
]}

Chantrell, RW ^{[1
]}

机构：

[1] Seagate Res, Pittsburgh, PA 15222 USA

来源：

EUROPHYSICS LETTERS | 2005年 / 69卷 / 05期

关键词：

D O I：

10.1209/epl/i2004-10404-2

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

A model of magnetic interactions in the ordered ferromagnetic FePt is proposed on the basis of first-principles calculations of non-collinear magnetic configurations and shown to be capable of explaining recent measurements of magnetic-anisotropy energy (MAE). The site (Fe, Pt) resolved contributions to the MAE have been distinguished with small Fe easy-plane and large Pt easy-axis terms. This model has been tested against available experimental data on the temperature dependence of MAE showing scaling of uniaxial MAE (K-1(T)) with magnetization (M(T)) K-1(T) similar to M(T)(gamma) characterized by the unusual exponent of gamma = 2.1. It is shown that this unusual behavior of the FePt can be quantitatively explained within the proposed model and originates from an effective anisotropic exchange mediated by the induced Pt moment. The latter is expected to be a common feature of 3d-5d(4d) alloys having 5d/4d elements with large spin-orbit coupling and exchange-enhanced Stoner susceptibility.

引用

页码：805 / 811

页数：7

共 23 条

[1] Competition between ferromagnetism and antiferromagnetism in FePt [J].