Magnetic Anisotropy in [Pt/Co]₄/MgO/[Co/Pt]₂ Multilayers

Abstract:

A serial of [Pt/Co]₄/MgO/[Co/Pt]₂ multilayers were prepared by magnetron sputtering in this study and Antiferromagnetic (AF) interlayer coupling was observed with increasing MgO spacer thickness. Perpendicular magnetic anisotropy of soft layer in [Pt/Co]₄/MgO/[Co/Pt]₂ multilayers were measured by Extraordinary Hall Effect (EHE). The direction of the magnetic field was parallel to the direction of the current. The results revealed that perpendicular magnetic anisotropy constant K_u oscillates with the thickness of MgO layer which is between 1.3 to 3.3 nm. The period of this oscillation is about 0.43 nm. This is very close to the monolayer (100) MgO. With increasing MgO spacer, the periodic variation of interface between [Pt/Co]_n and MgO layer may be one of the reasons for this oscillation behavior of K_u.

• Periodical: Materials Science Forum (Volume 944)
• Pages: 625-630
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.944.625
• Online since: January 2019
• Authors: Qian Li, Lei Li*, Wei Zhou, Jun Chen, Si Yuan Zhang, Jian Hua Cai
• Keywords: Antiferromagnetic Interlayer Coupling, Extraordinary Hall Effect, Perpendicular Magnetic Anisotropy, Perpendicular Magnetic Tunnel Junctions

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