  We develop the fluctuational electrodynamics of metamaterials with hyperbolic
dispersion and show the existence of broadband thermal emission beyond the
black body limit in the near field. This arises due to the thermal excitation
of unique bulk metamaterial modes, which do not occur in conventional media. We
consider a practical realization of the hyperbolic metamaterial and estimate
that the effect will be observable using the characteristic dispersion
(topological transitions) of the metamaterial states. Our work paves the way
for engineering the near-field thermal emission using metamaterials.
