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General $delta$-shell interactions for the two-dimensional Dirac operator: self-adjointness and approximation

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 نشر من قبل Biagio Cassano
 تاريخ النشر 2021
  مجال البحث فيزياء
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In this work we consider the two-dimensional Dirac operator with general local singular interactions supported on a closed curve. A systematic study of the interaction is performed by decomposing it into a linear combination of four elementary interactions: electrostatic, Lorentz scalar, magnetic, and a fourth one which can be absorbed by using unitary transformations. We address the self-adjointness and the spectral description of the underlying Dirac operator, and moreover we describe its approximation by Dirac operators with regular potentials.



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