1302.2965 (Yu Guo et al.)

Thermal Hyperbolic Metamaterials    [PDF]

Yu Guo, Zubin Jacob

We use Rytov's fluctuational electrodynamics to derive the thermal energy density and near-field thermal emission properties of artificial media with hyperbolic dispersion. The unique electromagnetic modes of such hyperbolic metamaterials (h-MMs) lead to broadband thermal emission beyond the black body limit in the near-field. We show that a practical phonon-polaritonic realization can be used to demonstrate the thermal properties of h-MMs. We also explain the phenomenon of thermal topological transitions in such practical metamaterials which can be used to experimentally isolate the thermal excitation of bulk metamaterial modes from other surface modes. Finally, we introduce the concept of near-field non-locality which is detrimental to any near-field property of metamaterials but show that our predicted effect survives these non-idealities including losses and dispersion. Our work has implications for thermal engineering using metamaterials including near-field super-planckian thermal energy transfer and near field thermophotovoltaics.

View original: http://arxiv.org/abs/1302.2965