http://www.m02group.com. Δ 1. Fe. AP. MgO. Cr. Fe. The effect of Cr interlayer in epitaxial Fe/MgO/Fe magnetic tunneling junctions by first principles calculations. J. Zhang, Y. Wang, X.-G. Zhang, X.F. Han. Group M02, State Key Laboratory of Magnetism Institute of Physics, CAS. Abstract.
The effect of Cr interlayer in epitaxial Fe/MgO/Fe magnetic tunneling junctions by first principles calculations
J. Zhang, Y. Wang, X.-G. Zhang, X.F. Han
Group M02, State Key Laboratory of Magnetism
Institute of Physics, CAS
The effect of Cr(001) interlayer in the single crystal Fe(001)/MgO/Cr (x=0–30 ML)/Fe magnetic tunneling junctions (MTJs) has been investigated by first-principles calculations. The tunneling magnetic resistance (TMR) oscillated with a 2 ML period as a function of the Cr(001) interlayer thickness. In some thickness range, the TMR oscillated between the positive and negative values and exhibit interesting odd-even effect.
Two feature of Cr (001):
(1)The structure of Fe(001)/MgO(001)/Fe MTJ with Cr (001) interlayer
(2) The decrease and 2 ML periodic oscillation of TMR (a)and the oscillation of resistance area (RA) (b) in epitaxial Fe/MgO/Cr/Fe (Ref. 1) MTJ.
(3) Tunneling conductance GP and GAP (a) and MR ratio (b) of MTJ calculated by LKKR first principles method.
(4)The transmission distribution in two dimension Brillouin zones for P majority ((a)-(e)) and AP ((f)-(g)) with Cr interlayer increasing from 2 to 6 ML
Our first principles calculations show that the Cr (001) is a metallic barrier for Δ1 electrons tunneling which causes the decrease and negative MR. The AFM order of Cr (001) causes the oscillation of P and AP conductance with a period of 2 ML.
 Rie Matsumoto et al., Phys. Rev. B. 79 (2009) 174436.
 F. Greullet et al.,Phys. Rev. Lett. 99 (2007) 187202.
 J. Zhang,Y. Wang, X.-G. Zhang, X.F. Han, to be submitted.
This work was supported by MOST, NSFC and CAS.