Dependence of domain wall pinning potential landscapes on domain wall chirality and pinning site geometry in planar nanowires

L. K. Bogart, D. Atkinson, K. O'Shea, D. McGrouther, S. McVitie
2009 Physical Review B  
S. (2009) 'Dependence of domain wall pinning potential landscapes on domain wall chirality and pinning site geometry in planar nanowires.', Physical review B., 79 (5). 054414. The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-profit purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record
more » ... in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full DRO policy for further details. We report on domain wall pinning behavior and the potential-energy landscapes created by notches of two different geometries in planar Permalloy nanowires. Domain wall depinning was probed experimentally using spatially resolved magneto-optical Kerr effect measurements. The spin structure of pinned domain walls was determined using Lorentz microscopy, and domain wall pinning behavior was also analyzed using micromagnetic simulations, which are in good qualitative agreement with experimental results. All notch structures have dimensions that are comparable with the domain wall length scales. For the notch structures investigated, the depinning field experienced by a domain wall is found to be relatively insensitive to notch geometry although the pinning behavior is highly sensitive to both the wall type and the wall chirality spin structure. Energetically, the notches present both potential barriers and/or potential wells depending on the micromagnetic structure of the domain wall, and we find that the chirality of the domain wall is a key determinant of the pinning potential landscape. The pinning behavior of domain walls is discussed in detail, and direct quantitative measurements of the width and depth of the potential wells and/or barriers responsible for domain wall pinning are given for vortex walls pinned in triangular and rectangular notches.
doi:10.1103/physrevb.79.054414 fatcat:g4lnw4p45jhfngm4riky2v6giu