Ultrabroadband Super-Planckian Radiative Heat Transfer with Profile-Patterned Hyperbolic Metamaterial

We demonstrate the possibility of ultrabroadband super-Planckian radiative heat transfer between two metal plates patterned with tapered hyperbolic metamaterial arrays. It is shown that, by employing profile-patterned hyperbolic media, one can design photonic bands to populate a desired thermal radiation window, with a spectral density of modes much higher than what can be achieved with unstructured media. For nanometer-sized gaps between two plates, the modes occupy states both inside and outside the light cone, giving rise to ultrabroadband super-Planckian radiative heat transfer. Our study reveals that structured hyperbolic metamaterial offers unprecedented potential in achieving a controllable super-Planckian radiative heat transfer. PACS numbers: 44.40.+a, 73.20.Mf