Towards a black body for near-field thermal radiation

TL;DR

This paper investigates near-field heat transfer in hyperbolic materials, showing they can support broadband modes for efficient photon tunnelling and potentially act as perfect nanoscale thermal emitters, approaching the blackbody limit.

Contribution

It introduces the concept of a near-field blackbody limit for hyperbolic materials, highlighting their potential for high-efficiency thermal emission at the nanoscale.

Findings

Hyperbolic materials support broadband frustrated modes for heat transfer.

These materials can be engineered to be near-perfect thermal emitters.

Near-field heat transfer can approach the blackbody limit with hyperbolic media.

Abstract

We study the near-field heat exchange between hyperbolic materials and demonstrate that these media are able to support broadband frustrated modes which transport heat by photon tunnelling with a high efficiency close to the theoretical limit. We predict that hyperbolic materials can be designed to be perfect thermal emitters at nanoscale and derive the near-field analog of the blackbody limit.