Bulk Layered Materials and Their Monolayer Counterparts for Radiative Heat Transfer

Thermal radiation between objects is a phenomenon that has applications in energy harvesting and heat management. In this study, we consider several layered bulk systems and their monolayer counterparts to broaden the materials perspective and highlight the role of dimensionality in radiative heat transfer phenomena. For this purpose, we calculate the exchanged thermal power by taking realistic electronic and optical response properties computed from first principles. Characteristic behaviors in terms of magnitude, scaling laws, and temperature dependence are analyzed by using analytically effective models based on the computational results for the optical response. We find that the dimensionality, hyperbolicity, and specific features of the optical response especially at low frequencies must be considered on equal footing in order to understand thermal radiation in realistic materials. This study suggests that structure–property relations from first principles are necessary in the search of optimum naturally occurring materials for radiative thermal control.