Exchange-coupled perpendicular media

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:321

Article

Suess, D.¹  Lee, J.¹  Fidler, J.¹  Schrefl, T.² 

[1] Vienna Univ Technol, Inst Solid State Phys, A-1040 Vienna, Austria

[2] Univ Sheffield, Dept Mat Engn, Sheffield, S Yorkshire, England

关键词: Graded medium;    Exchange spring medium;    Switching field distribution;    Exchange-coupled composite;    Gain of graded media;    Precessional switching;    Fast switching;    Phase diagram;   

DOI  :  10.1016/j.jmmm.2008.06.041

来源: Elsevier

【 摘 要 】

The potential of exchange spring bilayers and graded media is reviewed. An analytical model for the optimization of graded media gives an optimal value of the magnetic polarization of J(s) = 0.8 T. The optimum design allows for thermally stable grains with grain diameters in the order of 3.3 nm, which supports ultra-high density up to 5-10 Tbit/in(2). The switching. field distribution is significantly reduced in bilayer media and graded media compared to single-phase media. For the graded media the switching. field distribution is reduced by about a factor of two. For bilayer media the minimum switching. field distribution is obtained for soft-layer anisotropies that are about one. fifth of the hard-layer anisotropy. The influence of precessional switching on the reversal time and the reversal. field is investigated in detail for magnetic bilayers. Exchange spring bilayers can be reversed with. field pulses of 20 ps. (C) 2008 Elsevier B.V. All rights reserved.

【 授权许可】

Free