Artificial helical nanomagnets

A. A. Fraerman; B. A. Gribkov; S. A. Gusev; B. Hjorvarsson; A. Yu. Klimov; V. L. Mironov; D. S. Nikitushkin; V. V. Rogov; S. N. Vdovichev; H. Zabel

arXiv · 0705.2445

Artificial helical nanomagnets

A. A. Fraerman·B. A. Gribkov·S. A. Gusev·B. Hjorvarsson·A. Yu. Klimov·V. L. Mironov·D. S. Nikitushkin·V. V. Rogov·S. N. Vdovichev·H. Zabel

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Abstract

We demonstrate the existence of a helical state in patterned multilayer nanomagnets. The artificial helimagnets consist of a stack of single domain ferromagnetic disks separated by insulating nonmagnetic spacers. The spiral state is shown to originate from the magnetostatic interaction between nearest and next nearest neighbouring single-domain disks in the stack. Since the magnetostatic interaction for such disks is rather strong, the helical state should be stable at room temperature. The helimagnets were fabricated from a [Co/Si]*3 multilayer using electron beam lithography. The helical state was confirmed by a magnetic stray field analysis using magnetic force microscopy.

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A. A. Fraerman, B. A. Gribkov, S. A. Gusev, B. Hjorvarsson, A. Yu. Klimov, V. L. Mironov, D. S. Nikitushkin, V. V. Rogov, S. N. Vdovichev, H. Zabel. 2007-05-17. Artificial helical nanomagnets. https://arxiv.org/abs/0705.2445

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