Magnetic tunnel junctions using Co/Ni multilayer electrodes with perpendicular magnetic anisotropy

Ia Lytvynenko (1) , C. Deranlot (2) , Stéphane Andrieu (3) , Thomas Hauet (3)

1 Sumy State University
2 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)
3 IJL - Institut Jean Lamour

Magnetic and magneto-transport properties of amorphous Al2O3-based magnetic tunnel junctions (MTJ) having two Co/Ni multilayer electrodes exhibiting perpendicular magnetic anisotropy (PMA) are presented. An additional Co/Pt multilayer is required to maintain PMA in the top Co/Ni electrode. Slight stacking variations lead to dramatic magnetic changes due to dipolar interactions between the top and bottom electrodes. Tunnel magneto-resistance (TMR) of up to 8% at 300K is measured for the MTJ with two PMA electrodes. The TMR value increases when the top PMA electrode is replaced by an in-plane magnetized Co layer. These observations can be attributed to significant intermixing in the top Co/Ni electrode.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Ia Lytvynenko, C. Deranlot, Stéphane Andrieu, Thomas Hauet. Magnetic tunnel junctions using Co/Ni multilayer electrodes with perpendicular magnetic anisotropy. Journal of Applied Physics, 2015, 117 (5), pp.053906. ⟨10.1063/1.4906843⟩. ⟨hal-01284019⟩