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Studies of Current-Driven Excitations in Co/Cu/Co Trilayer Nanopillars

S. Urazhdin·Norman O. Birge·W. P. Pratt Jr·J. Bass
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Abstract

We measure the dynamic resistance of a Co/Cu/Co trilayer nanopillar at varied magnetic field $H$ and current $I$. The resistance displays the usual behavior, almost symmetric in $H$, both when magnetization switching is hysteretic at small $I,H$, and reversible at larger $I,H$. We show differences in the $I,H$ magnetization stability diagram measured by holding $I$ fixed and varying $H$ and vice versa. We also show how the peak in $dV/dI$ associated with telegraph noise in the reversible switching regime, is calculated from the telegraph noise variations with $I$. Lastly, we show data for a similar sample that displays behavior asymmetric in $H$, and a negative reversible switching peak instead of a usual positive one.

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S. Urazhdin, Norman O. Birge, W. P. Pratt Jr, J. Bass. 2003-10-20. Studies of Current-Driven Excitations in Co/Cu/Co Trilayer Nanopillars. https://arxiv.org/abs/cond-mat/0310472

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