Enhancement and Manipulation of Near-Field Radiative Heat Transfer Using an Intermediate Modulator

Many efforts have been dedicated to enhancing near-field radiative heat transfer by designing different kinds of geometric shapes or introducing new materials. Besides just improving the heat-transfer rate, active and convenient thermal management is also important in micro- and nanothermal systems. We show that the introduction of an intermediate modulator, based on the graphene/h-BN/graphene heterostructure, can enhance and manipulate thermal radiative heat transfer without changing the distance or other parameters of the emitter and absorber. Such three-body systems can increase the radiatively exchanged power several times over corresponding two-body counterparts. The introduced modulator can be viewed as a midrepeater to effectively enhance photon tunneling through evanescent modes. Furthermore, the heat-transfer rate can be modulated over a large range and can even be lower than that in two-body systems through the application of bias voltages. The mechanism can be explained by the change of energy-transmission coefficients between bodies through adjustment of the optical properties of graphene. The presented scheme may open a promising avenue for the active control of near-field heat transfer at the micro- and nanoscales.