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arXiv · 1910.13837

Ultra-low switching current density in all-amorphous W-Hf / CoFeB / TaOx films

Katharina Fritz·Lukas Neumann·Markus Meinert
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Abstract

We study current-induced deterministic magnetization switching and domain wall motion via polar Kerr microscopy in all-amorphous W$_{66}$Hf$_{34}$/CoFeB/TaO$_\text{x}$ with perpendicular magnetic anisotropy and large spin Hall angle. Investigations of magnetization switching as a function of in-plane assist field and current pulse-width yield switching current densities as low as $3\times 10^{9}$ A/m$^2$. We accredit this low switching current density to a low depinning current density, which was obtained from measurements of domain wall displacements upon current injection. This correlation is verified by investigations of a Ta/CoFeB/MgO/Ta reference sample, which showed critical current densities of at least one order of magnitude larger, respectively.

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Katharina Fritz, Lukas Neumann, Markus Meinert. 2020-08-24. Ultra-low switching current density in all-amorphous W-Hf / CoFeB / TaOx films. https://doi.org/10.1103/physrevapplied.14.034047

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