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arXiv · 1401.2266

Thermally activated switching of perpendicular magnet by spin-orbit spin torque

Ki-Seung Lee·Seo-Won Lee·Byoung-Chul Min·Kyung-Jin Lee
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Abstract

We theoretically investigate the threshold current for thermally activated switching of a perpendicular magnet by spin-orbit spin torque. Based on the Fokker-Planck equation, we obtain an analytic expression of the switching current, in agreement with numerical result. We find that thermal energy barrier exhibits a quasi-linear dependence on the current, resulting in an almost linear dependence of switching current on the log-scaled current pulse-width even below 10 ns. This is in stark contrast to standard spin torque switching, where thermal energy barrier has a quadratic dependence on the current and the switching current rapidly increases at short pulses. Our results will serve as a guideline to design and interpret switching experiments based on spin-orbit spin torque

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Ki-Seung Lee, Seo-Won Lee, Byoung-Chul Min, Kyung-Jin Lee. 2014-01-10. Thermally activated switching of perpendicular magnet by spin-orbit spin torque. https://doi.org/10.1063/1.4866186

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