Non-Hermitian dislocation modes: Stability and melting across exceptional points

  title={Non-Hermitian dislocation modes: Stability and melting across exceptional points},
  author={Archisman Panigrahi and Roderich Moessner and Bitan Roy},
  journal={Physical Review B},
The traditional bulk-boundary correspondence assuring robust gapless modes at the edges and surfaces of insulating and nodal topological materials gets masked in non-Hermitian (NH) systems by the skin effect, manifesting an accumulation of a macroscopic number of states near such interfaces. Here we show that dislocation lattice defects are immune to such skin effect or at most display a weak skin effect (depending on its relative orientation with the Burgers vector), and as such they support… 

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