On Modeling Perfectly Conducting Sharp Corners With Magnetically Inert   Dielectrics Of Extreme Complex Permittivities
  The idea of replacing an edgy perfectly conducting boundary by the corresponding interface filled with a dielectric material of extreme complex permittivities, is examined in the present work. A semi-analytical solution to the corresponding boundary value problems is obtained and the merit of the modeling has been checked. Certain conclusions for the effect of the constituent material parameters and the geometric features of the configuration on the model effectiveness, are drawn and discussed. 
Constantinos A. Valagiannopoulos and Ari Sihvola
physics.class-ph