Total transmission of electromagnetic waves at interfaces associated with an indefinite medium

We investigate the problem of total transmission at the interface separating an isotropic regular material and an indefinite medium [Phys. Rev. Lett.90, 077405 (2003)] in which not all of the principal elements of the permeability and permittivity tensors have the same sign, for TE- and TM-polarized electromagnetic waves. We make a detailed investigation on the existence conditions of total transmission and the corresponding Brewster's angles when an electromagnetic wave is incident on the interface from an isotropic regular material. We show that the propagation characteristics of electromagnetic waves at such interfaces are quite different from those at regular interfaces. For both TE and TM waves, total transmission is possible at the interfaces containing an indefinite medium; in particular, normally incident total transmission and omnidirectional total transmission are also allowed, provided that suitable physical parameters for the two materials across the interface are chosen.