Surface pinning and triggered unwinding of skyrmions in a cubic chiral magnet

  title={Surface pinning and triggered unwinding of skyrmions in a cubic chiral magnet},
  author={Peter Milde and Erik Neuber and Andreas Bauer and Christian Pfleiderer and Lukas M. Eng},
  journal={Physical Review B},
In the cubic chiral magnet Fe1−xCoxSi a metastable state comprising of topologically nontrivial spin whirls, so-called skyrmions, may be preserved down to low temperatures by means of field cooling the sample. This metastable skyrmion state is energetically separated from the topologically trivial ground state by a considerable potential barrier, a phenomenon also referred to as topological protection. Using magnetic force microscopy on the surface of a bulk crystal, we show that certain… 

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