Refractive index and wave vector in passive or active media

Resolving the wave vector in negative refractive index media.

We address the general issue of resolving the wave vector in complex electromagnetic media including negative refractive media. This requires us to make a physical choice of the sign of a square root imposed merely by conditions of causality. By considering the analytic behavior of the wave vector in the complex plane, it is shown that there are a total of eight physically distinct cases in the...

On resolving the refractive index and the wave vector.

The identification of the refractive index and the wave vector for general (possibly active) linear, isotropic, homogeneous, and nonspatially dispersive media is discussed. Correct conditions for negative refraction necessarily include the global properties of the permittivity and permeability functions epsilon=epsilon(omega) and mu=mu(omega). On the other hand, a necessary and sufficient condi...

Fresnel equations and the refractive index of active media.

A class of realizable active media exists for which the refractive index cannot be defined as an analytic function in the upper half-plane of complex frequency. The conventional definition of the refractive index based on analyticity is modified such that it is valid for active media in general, and associated Fresnel equations are proved. In certain active media, the presence of a "backward" w...

Refractive-index measurement of absorbing condensed media.

Broadband, Volumetric Negative-Refractive-Index Media

Broadband, Volumetric Negative-Refractive-Index Media by Scott M. Rudolph Chair: Anthony Grbic Since their invention, negative-refractive-index (NRI) media have been plagued by three primary limitations: narrow bandwidth, high loss and polarization dependence. In this thesis, each of these problems is addressed. First, a new metamaterial topology that achieves negative permeability over a broad...