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arXiv · 1604.08186

Spin- and Symmetry-Filtering Combined Tunnel Magnetoresistance through Epitaxial MgO/EuS Tunnel Barriers

Zhiwei Gao·Yihang Yang·Fen Liu·Qian Xue·Guo-Xing Miao
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Abstract

We created epitaxial magnetic tunnel junctions of FeCo/MgO/EuS on MgO buffered Si (100). Tunnel magnetoresistance reached up to 64% at 4.2 K. An unexpected fast drop of magnetoresistance was recorded for MgO thickness above 1 nm, which is attributed to the forced nonspecular conductance across the EuS conduction band minimum located at the X point, rather than the desired Delta_1 conductance centered around the Gamma point.

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Zhiwei Gao, Yihang Yang, Fen Liu, Qian Xue, Guo-Xing Miao. 2016-04-27. Spin- and Symmetry-Filtering Combined Tunnel Magnetoresistance through Epitaxial MgO/EuS Tunnel Barriers. https://arxiv.org/abs/1604.08186

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