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arXiv · 1403.2126

Effective anisotropy gradient in pressure graded [Co/Pd] multilayers

B. J. Kirby·P. K. Greene·B. B. Maranville·J. E. Davies·Kai Liu
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Abstract

A vertically graded anisotropy profile has been proposed as an optimized balance of low coercivity and thermal stability for multilayers used in magnetic media. Deposition pressure is known to have a profound effect on the magnetic reversal properties of Co/Pd multilayers, making it an attractive control parameter for achieving an anisotropy gradient. We have used polarized neutron reflectometry to study the depth-dependent reversal behavior of "pressure-graded" Co/Pd, and observed pronounced gradients in the saturation magnetization and in the rate at which magnetization changes with field (the effective anisotropy). While the anisotropy gradient likely arises from a combination of factors intrinsic to deposition pressure, micromagnetic simulations indicate that the observed saturation magnetization gradient alone has a major effect on the resulting coercivity.

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B. J. Kirby, P. K. Greene, B. B. Maranville, J. E. Davies, Kai Liu. 2014-03-20. Effective anisotropy gradient in pressure graded [Co/Pd] multilayers. https://doi.org/10.1063/1.4908140

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