Title :
Spontaneously Formed FePt Graded Granular Media With a Large Gain Factor
Author :
Hao Wang ; Haibao Zhao ; Ugurlu, O. ; Jian-Ping Wang
Author_Institution :
Dept. of Electr. & Comput. Eng, Univ. of Minnesota, Minneapolis, MN, USA
fDate :
7/4/1905 12:00:00 AM
Abstract :
In conventional magnetic recording media fabrication processes, magnetically soft regions of composite or graded material are prepared by varying either the substrate temperature or the film composition during deposition. In this work, ultrathin FePt granular media with graded composition was fabricated directly by spontaneous layer diffusion between FePt and Pt layers during the film deposition. Electron energy loss spectroscopy analysis on individual FePt columnar grains identified the composition distribution of Fe and confirmed the Fe composition gradient. A large “gain factor” of 3.74, indicative of a relatively high-thermal energy barrier, was obtained in this spontaneously formed FePt graded granular media.
Keywords :
electron energy loss spectra; granular materials; iron alloys; magnetic recording; platinum alloys; FePt; deposition; electron energy loss spectroscopy; film composition; gain factor; magnetic recording media; magnetically soft regions; spontaneous layer diffusion; spontaneously formed graded granular media; substrate temperature; thermal energy barrier; Coercive force; Copper; Iron; Nonhomogeneous media; Perpendicular magnetic recording; FePt; Information storage; diffusion process; exchange coupled composite (ECC) media; gain factor; graded media; magnetic recording;
Journal_Title :
Magnetics Letters, IEEE
DOI :
10.1109/LMAG.2012.2188133