Uniaxial dielectric mediums with hyperbolic dispersion relations

The dispersion relations for conventional uniaxial dielectric mediums may be characterized as elliptical or elliptical–like, according to whether the medium is nondissipative or dissipative, respectively. However, under certain constitutive parameter regimes, the dispersion relations may be hyperbolic or hyperbolic–like. We investigate planewave propagation in a hyperbolic/hyperbolic–like uniaxial dielectric medium. For both evanescent and nonevanescent propagation, the phase velocity is found to be positive with respect to the time–averaged Poynting vector. A conceptualization of a hyperbolic–like uniaxial medium as a homogenized composite medium is presented.