Feedback control of noise in spin valves by the spin-transfer torque

Swarnali Bandopadhyay; Arne Brataas; Gerrit E. W. Bauer

doi:10.1063/1.3556270

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arXiv · 1010.4954

Feedback control of noise in spin valves by the spin-transfer torque

Swarnali Bandopadhyay·Arne Brataas·Gerrit E. W. Bauer

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Abstract

The miniaturisation of magnetic read heads and random access memory elements makes them vulnerable to thermal fluctuations. We demonstrate how current-induced spin-transfer torques can be used to suppress the effects of thermal fluctuations. This enhances the fidelity of perpendicular magnetic spin valves. The simplest realization is a dc current to stabilize the free magnetic layers. The power can be significantly reduced without losing fidelity by simple control schemes, in which the stabilizing current-induced spin-transfer torque is controlled by the instantaneous resistance.

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Swarnali Bandopadhyay, Arne Brataas, Gerrit E. W. Bauer. 2010-10-24. Feedback control of noise in spin valves by the spin-transfer torque. https://doi.org/10.1063/1.3556270

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