Mechanism of higher order contributions in interface anisotropy of thin films: FeCo/MgO case

Author

Barker, J. ; Kalitsov, A. ; Singh, A. ; Mryasov, O.N. ; Okatov, S.

Author_Institution

Inst. for Mater. Res., Tohoku Univ., Sendai, Japan

fYear

2015

fDate

11-15 May 2015

Firstpage

1

Lastpage

1

Abstract

Current state of the art perpendicular magnetic tunnel junctions (pMTJs) rely upon a large uniaxial interface anisotropy to overcome the demagnetizing field. Experimental measurements have found that as well as the expected K1sin2(θ) anisotropy energy, a higher order K2sin4(θ) contribution is present. In thin films with bulk anisotropies K2 can arise from a distribution of the anisotropy axes. In the course of constructing a model of FeCo/MgO we unexpectedly found a K2sin4(θ) dependence in the free energy, even without any disorder in the anisotropy axes or higher order magneto-crystalline anisotropy.

Keywords

cobalt alloys; interface magnetism; iron alloys; magnesium compounds; magnetic anisotropy; magnetic thin films; FeCo-MgO; free energy; perpendicular magnetic tunnel junctions; thin films; uniaxial interface anisotropy; Anisotropic magnetoresistance; Films; Magnetic tunneling; Magnetization; Monte Carlo methods; Perpendicular magnetic anisotropy;

fLanguage

English

Publisher

ieee

Conference_Titel

Magnetics Conference (INTERMAG), 2015 IEEE

Conference_Location

Beijing

Print_ISBN

978-1-4799-7321-7

Type

conf

DOI

10.1109/INTMAG.2015.7157633

Filename

7157633