Modern fabrication technology has enabled the study of submicron ferromagnetic strips with a particularly simple domain structure, allowing single, well-defined domain walls to be isolated and characterized. However, these domain walls have complex field-driven dynamics. The wall velocity initially increases with field, but above a certain threshold the domain wall abruptly slows down, accompanied by periodic transformations of the domain wall structure. This behaviour is potentially detrimental to the speed and proper functioning of proposed domain-wall-based devices1,2,3, and although methods for suppression of the breakdown have been demonstrated in simulations4,5, a convincing experimental demonstration is lacking. Here, we show experimentally that a series of cross-shaped traps acts to prevent transformations of the domain wall structure and increase the domain wall velocity by a factor of four compared to the maximum velocity on a plain strip. Our results suggest a route to faster and more reliable domain wall devices for memory, logic and sensing.
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The OOMMF code is available at http://math.nist.gov/oommf.
This work was supported by the European Community under the Sixth Framework Programme SPINSWITCH MRTN-CT-2006-035327.
The authors declare no competing financial interests.
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Lewis, E., Petit, D., O’Brien, L. et al. Fast domain wall motion in magnetic comb structures. Nature Mater 9, 980–983 (2010). https://doi.org/10.1038/nmat2857
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