The magnetic remanent states and switching behavior of Fe thin-film split-rings are investigated using magnetic force microscopy, magnetoresistance measurements, and micromagnetic simulations in order to assess their suitability as spin-filter contacts for spin field-effect-transistors. The gaps between the two halves of each ring are found to absorb then emit domain walls and act as pinning sites for “virtual” domain walls so that the observed switching mechanisms are similar to those of continuous rings. It is shown that these rings offer advantages over rectangular spin-filter contacts owing to their reduced stray fields and easy accessibility of the necessary magnetic states.
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