Graphene-Based Active Modulation of Near Field Thermal Radiation*

Modern heat switches for thermal regulation of electronics or refrigeration systems require mechanical components, either as pumps to transport a working fluid or as thermally conducting mechanical linkages. Such systems are difficult to apply at sufficiently small length scales and lack the reliability of non-mechanical systems. Here, we theoretically propose and experimentally demonstrate the modulation of heat flow in a solid-state system using near-field radiative effects. Modulating the carrier concentration in graphene using electrostatic gating enables the radiative flux to another graphene sheet to be actively tuned. Our work highlights the capability for active control of radiative heat flow using electrical biasing of atomically thin films.