  Excitation of hybrid modes constituted by different material-supported
polaritons is a common way to enhance the near-field radiative energy
transport, which has fascinating promise in applications of thermal photonics.
Here, we investigate near-field thermal radiation mechanisms in heterostructure
composed of hBN film and black phosphorus single layer. The results show that
this heterostructured system can give rise to a remarkable enhancement for
photon tunneling, outperforming the near-field thermal radiation properties of
its building blocks, as well as some other representative heterostructures.
Moreover, we find that the anisotropic hybrid effect can induce a remarkable
topological reconstitution of polaritons for hBN film and black phosphorus,
forming a novel anisotropic hybrid polaritons. Notably, such hybrid modes show
significant topological differences compared to hBN film and black phosphorus
in the type-I Reststrahlen band due to the anisotropic anticrossing
hybridization effect. Lastly, we systematically analyze the evolution of such
hybrid polariton modes as a function of hBN film thickness and the
corresponding influence on radiative properties of the heterostructure. This
work may benefit the applications of near-field energy harvesting and radiative
cooling based on hybrid polaritons in anisotropic two-dimensional material and
hyperbolic film.
