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arXiv · 1205.3666

Spin transport and spin dephasing in zinc oxide

Matthias Althammer·Eva-Maria Karrer-Müller·Sebastian T. B. Goennenwein·Matthias Opel·Rudolf Gross
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Abstract

The wide bandgap semiconductor ZnO is interesting for spintronic applications because of its small spin-orbit coupling implying a large spin coherence length. Utilizing vertical spin valve devices with ferromagnetic electrodes (TiN/Co/ZnO/Ni/Au), we study the spin-polarized transport across ZnO in all-electrical experiments. The measured magnetoresistance agrees well with the prediction of a two spin channel model with spin-dependent interface resistance. Fitting the data yields spin diffusion lengths of 10.8nm (2K), 10.7nm (10K), and 6.2nm (200K) in ZnO, corresponding to spin lifetimes of 2.6ns (2K), 2.0ns (10K), and 31ps (200K).

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Matthias Althammer, Eva-Maria Karrer-Müller, Sebastian T. B. Goennenwein, Matthias Opel, Rudolf Gross. 2012-08-27. Spin transport and spin dephasing in zinc oxide. https://doi.org/10.1063/1.4747321

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