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arXiv · 0910.2489

Voltage Asymmetry of Spin-Transfer Torques

Deepanjan Datta·Behtash Behin-Aein·Sayeef Salahuddin·Supriyo Datta
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Abstract

We present a Non-Equilibrium Green's Function based model for spin torque transfer (STT) devices which provides quantitative agreement with experimentally measured (1) differential resistances, (2) Magnetoresistance (MR), (3) In-plane torque and (4) out-of-plane torque over a range of bias voltages, using a single set of three adjustable parameters. We believe this is the first theoretical model that is able to cover this diverse range of experiments and a key aspect of our model is the inclusion of multiple transverse modes. We also provide a simple explanation for the asymmetric bias dependence of the in-plane torque, based on the polarization of the two contacts in energy range of transport.

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Deepanjan Datta, Behtash Behin-Aein, Sayeef Salahuddin, Supriyo Datta. 2009-10-13. Voltage Asymmetry of Spin-Transfer Torques. https://arxiv.org/abs/0910.2489

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