Halfvortices in Flat Nanomagnets

  • Gia-Wei Chern
  • David Clarke
  • Hyun Youk
  • Oleg Tchernyshyov
Conference paper
Part of the NATO Science for Peace and Security Series book series (NAPSB)

Abstract

We discuss a new type of topological defect in XY systems for which the O (2) symmetry is broken in the presence of a boundary. Of particular interest is the appearance of such defects in nanomagnets with a planar geometry. They are manifested as kinks of magnetization along the edge and can be viewed as halfvortices with winding numbers ±1/2. We argue that the halfvortices play a role in flat nanomagnetics equally important to that of ordinary bulk vortices. We show that domain walls found in experiments and numerical simulations in strips and rings are composite objects containing two or more elementary defects. We also discuss a closely related system: the two-dimensional smectic liquid crystal films with planar boundary condition.

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Copyright information

© Springer Science + Business Media B.V. 2008

Authors and Affiliations

  • Gia-Wei Chern
    • 1
  • David Clarke
    • 1
  • Hyun Youk
    • 2
  • Oleg Tchernyshyov
    • 1
  1. 1.Department of Physics and AstronomyThe Johns Hopkins UniversityBaltimoreUSA
  2. 2.Department of PhysicsMassachusetts Institute of TechnologyCambridgeUSA

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