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Equivalence between vortices, twists and chiral gauge fields in Kitaevs honeycomb lattice model

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 نشر من قبل Matthew Horner Mr
 تاريخ النشر 2020
  مجال البحث فيزياء
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We demonstrate that $mathbb{Z}_2$ gauge transformations and lattice deformations in Kitaevs honeycomb lattice model can have the same description in the continuum limit of the model in terms of chiral gauge fields. The chiral gauge fields are coupled to the Majorana fermions that satisfy the Dirac dispersion relation in the non-Abelian sector of the model. For particular values, the effective chiral gauge field becomes equivalent to the $mathbb{Z}_2$ gauge field, enabling us to associate effective fluxes to lattice deformations. Motivated by this equivalence, we consider Majorana-bounding $pi$ vortices and Majorana-bounding lattice twists and demonstrate that they are adiabatically connected to each other. This equivalence opens the possibility for novel encoding of Majorana-bounding defects that might be easier to realise in experiments.

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