Exchange coupling strength in synthetic ferrimagnetic media

Author

Inomata, Akihiro ; Abarra, E.N. ; Acharya, B.R. ; Akimoto, H. ; Okamoto, I.

Author_Institution

Fujitsu Labs. Ltd., Atsugi, Japan

Volume

37

Issue

4

fYear

2001

fDate

7/1/2001 12:00:00 AM

Firstpage

1449

Lastpage

1451

Abstract

The antiferromagnetic exchange coupling strength (H_ex) between two CoCrPtB magnetic layers in bilayer synthetic ferrimagnetic media (SFM) is investigated. H_ex is found to be inversely proportional to the thickness and magnetization of the initial magnetic layer (L1). H_ex also shows a decrease with increasing temperature. An exchange coupling strength of J≈0.05 erg/cm² was obtained from H_ex. For further improvement of thermal stability at higher recording densities, the thickness or magnetic anisotropy of L1 may be increased. On the other hand, for an effective SFM, the coercivity of L1 must be lower than H_ex. Therefore, a large H_ex is critical for better thermal stabilization

Keywords

boron alloys; chromium alloys; cobalt alloys; coercive force; exchange interactions (electron); magnetic anisotropy; magnetic hysteresis; magnetic multilayers; magnetic recording; magnetic switching; platinum alloys; remanence; thermal stability; CoCrPtB; antiferromagnetic exchange coupling strength; coercivity; hysteresis loop; initial magnetic layer thickness; magnetic anisotropy; magnetic recording media; remanent magnetization; synthetic ferrimagnetic media; thermal stability; Antiferromagnetic materials; Coercive force; Couplings; Ferrimagnetic materials; Magnetic anisotropy; Magnetic recording; Magnetization; Perpendicular magnetic anisotropy; Temperature; Thermal stability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.950867

Filename

950867