info:eu-repo/semantics/article
Weakly bound states in heterogeneous waveguides
Fecha
2016-07Registro en:
Amore, Paolo; Fernández, Francisco Marcelo; Hoffman, Christoph P.; Weakly bound states in heterogeneous waveguides; Springer; European Physical Journal B - Condensed Matter; 89; 7; 7-2016; 163-180
1434-6028
1434-6036
CONICET Digital
CONICET
Autor
Amore, Paolo
Fernández, Francisco Marcelo
Hoffman, Christoph P.
Resumen
We study the spectrum of the Helmholtz equation in a two-dimensional infinite waveguide, containing a weak heterogeneity localized at an internal point, and obeying Dirichletboundary conditions at its border. We use the variational theorem to derive the conditionfor which the lowest eigenvalue of the spectrum falls below the continuum threshold and abound state appears, localized at the heterogeneity. We devise a rigorous perturbationscheme and derive the exact expression for the energy to third order in theheterogeneity.