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Room temperature domain wall pinning in bent ferromagnetic nanowires

D. M. Silevitch·M. Tanase·C. L. Chien·D. H. Reich
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Abstract

Mechanically bent nickel nanowires show clear features in their room temperature magnetoresistance when a domain wall is pinned at the location of the bend. By varying the direction of an applied magnetic field, the wire can be prepared either in a single-domain state or a two-domain state. The presence or absence of the domain wall acts to shift the switching fields of the nanowire. In addition, a comparison of the magnetoresistance of the nanowire with and without a domain wall shows a shift in the resistance correlated with the presence of a wall. The resistance is decreased by 20-30 milli-Ohms when a wall is present, compared to an overall resistance of 40-60 Ohms. A model of the magnetization was developed that allowed calculation of the magnetostatic energy of the nanowires, giving an estimate for the nucleation energy of a domain wall.

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D. M. Silevitch, M. Tanase, C. L. Chien, D. H. Reich. 2003-08-27. Room temperature domain wall pinning in bent ferromagnetic nanowires. https://arxiv.org/abs/cond-mat/0308579

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