Tunnel magnetoresistance in fully epitaxial MgO double barrier magnetic tunnel junctions

Author

Nozaki, T. ; Hirohata, A. ; Tezuka, N. ; Sugimoto, S. ; Inomata, K.

Author_Institution

Graduate Sch. of Eng., Tohoku Univ., Sendai, Japan

fYear

2005

fDate

4-8 April 2005

Firstpage

1981

Lastpage

1982

Abstract

The TMR properties of epitaxial Fe(100)/MgO(100)/Fe(100)/MgO(100)/Fe(100) double barrier magnetic tunnel junctions (DMTJs) is reported. Both TMR and I-V characteristics were measured at room temperature using a dc four probe method. Single barrier MTJs (SMTJs) were used as references. A pseudo-spin-valve type TMR curve originated from the different magnetic switching fields (H_sw) for the both top and bottom Fe layers (H_sw = 48 Oe) and for the middle Fe layer (H^sw = 14 Oe). Higher TMR ratios of up to 110% (average: 89%) compared with the SMTJ (average: 77%) are observed for the DMTJ although the magnitude of the TMR ratio for the DMTJ has been reported to be smaller than that for the SMTJs.

Keywords

iron; magnesium compounds; magnetic epitaxial layers; magnetic switching; spin valves; tunnelling magnetoresistance; Fe-MgO-Fe-MgO-Fe; I-V characteristics; TMR; dc four probe method; fully epitaxial double barrier magnetic tunnel junctions; magnetic switching fields; pseudospin-valve type TMR curve; single barrier MTJ; tunnel magnetoresistance; Amorphous magnetic materials; Amorphous materials; Iron; Magnetic field measurement; Magnetic tunneling; Materials science and technology; Molecular beam epitaxial growth; Random access memory; Temperature; Tunneling magnetoresistance;

fLanguage

English

Publisher

ieee

Conference_Titel

Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International

Print_ISBN

0-7803-9009-1

Type

conf

DOI

10.1109/INTMAG.2005.1464429

Filename

1464429