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Topological energy bounds for frustrated magnets

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 نشر من قبل Derek Harland
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف Derek Harland




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Frustrated magnets are known to support two-dimensional topological solitons, called skyrmions. A continuum model for frustrated magnets has recently been shown to support both two-dimensional skyrmions and three-dimensional knotted solitons (hopfions). In this note we derive lower bounds for the energies of these solitons expressed in terms of their topological invariants. The bounds are linear in the degree in the case of skyrmions and scale as the Hopf degree to the power 3/4 in the case of hopfions.



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