Scaling of coercivity in a 3d random anisotropy model

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:384

Article

Proctor, T. C.¹  Chudnovsky, E. M.¹  Garanin, D. A.¹ 

[1] CUNY, Dept Phys, Lehman Coll, Bronx, NY 10468 USA

关键词: Sintered magnet;    Amorphous magnet;    Magnetic hysteresis;    Random magnetic anisotropy;    Coercive field;   

DOI  :  10.1016/j.jmmm.2015.02.047

来源: Elsevier

【 摘 要 】

The random-anisotropy Heisenberg model is numerically studied on lattices containing over ten million spins. The study is focused on hysteresis and metastability due to topological defects, and is relevant to magnetic properties of amorphous and sintered magnets. We are interested in the limit when ferromagnetic correlations extend beyond the size of the grain inside which the magnetic anisotropy axes are correlated. In that limit the coercive field computed numerically roughly scales as the fourth power of the random anisotropy strength and as the sixth power of the grain size. Theoretical arguments are presented that provide an explanation of numerical results. Our findings should be helpful for designing amorphous and nanosintered materials with desired magnetic properties. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free