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arXiv · 0811.0245

Domain wall propagation in Permalloy nanowires with a thickness gradient

O. Petracic·P. Szary·H. Zabel·D. Goerlitz·K. Nielsch
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Abstract

The domain wall nucleation and motion processes in Permalloy nanowires with a thickness gradient along the nanowire axis have been studied. Nanowires with widths, w = 250 nm to 3 um and a base thickness of t = 10 nm were fabricated by electron-beam lithography. The magnetization hysteresis loops measured on individual nanowires are compared to corresponding nanowires without a thickness gradient. The Hc vs. t/w curves of wires with and without a thickness gradient are discussed and compared to micromagnetic simulations. We find a metastability regime at values of w, where a transformation from transverse to vortex domain wall type is expected.

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O. Petracic, P. Szary, H. Zabel, D. Goerlitz, K. Nielsch. 2008-12-12. Domain wall propagation in Permalloy nanowires with a thickness gradient. https://doi.org/10.1016/j.spmi.2009.08.001

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