Magnetization of Thin-Film Permalloy Ellipses used for Programmable Motion of Magnetic Particles

Simulations of magnetic microstructure in elliptical Permalloy elements used for controlled motion of magnetic particles are discussed. The saturating field of the elliptical elements was studied with respect to lateral dimensions for one-vortex, cross-tie, diamond and double-diamond states as initial zero-field domain configurations. With aspect ratio of 1:3 the short axis was varied from 125 nm to 1000 nm, whereas the thickness was kept constant at 50 nm.

Authors:

• P. Warnicke

Keywords:

• Domain structure
• magnetization
• micromagnetics
• Permalloy.

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