Super-Planckian thermal emission from a hyperlens

TL;DR

This paper proposes a hyperlens-based approach to significantly enhance thermal emission beyond black-body limits, enabling more efficient radiative cooling and energy systems at microscale.

Contribution

It introduces a theoretical method using an infrared hyperlens to amplify thermal radiation from small emitters beyond traditional limits.

Findings

Hyperlens converts near fields into propagating waves.

Thermal radiance exceeds black-body limit.

Potential applications in microscale cooling and energy systems.

Abstract

We suggest and theoretically explore a possibility to strongly enhance the steady thermal radiation of a small thermal emitter using an infrared hyperlens. The hyperbolic metamaterial of the hyperlens converts emitter's near fields into the propagating waves which are efficiently irradiated from the hyperlens surface. Thus, with the hyperlens, emitter's spectral radiance goes well beyond the black-body limit for the same emitter in free space. Although the hyperlens can be kept at a much lower temperature than the emitter, the whole structure may radiate, in principle, as efficiently as a black body with the same size as that of the hyperlens and the same temperature as that of the emitter. We believe that this study can lead to a breakthrough in radiative cooling at microscale, which is crucial for microlasers and microthermophotovoltaic systems.