We derive an approach to determine the causal direction of wavevectors of modes in optical metamaterials, which, in turn, determines signs of refractive index and impedance as a function of real and imaginary parts of dielectric permittivity and magnetic permeability. We use the developed technique to demonstrate that the interplay...
This dissertation concerns a broad range of unique phenomena related to the light propagation at nano- and micro-scales. To access the nano-domain, we introduce anisotropy-based waveguides with positive- and negative-index modes. These novel structures allow energy propagation in subwavelength regions and, in contrast to surface waves, have the mode structure...