Active control and enhancement of near-field heat transfer between dissimilar materials by strong coupling effects

Near-field radiative heat transfer (NFRHT) between dissimilar materials is important for near-field applications, such as near-field photonic thermal diode and nanoscale thermal imaging. It is demonstrated that monolayer graphene lead to a significant enhancement in the NFRHT between dissimilar materials. The presence of graphene is not only able to permit a large variation and amplification of NFRHT through its chemical potential, but also to fully compensate the mismatch between the resonance frequencies of the two dissimilar materials. And then we investigate the role of the strong coupling effects among different surface polaritonic modes on NFRHT. Especially, we identify strongly coupled polaritonic modes with considerable Rabi frequencies. Therefore, we analyze the graphene-assisted configurations by calculating both the near-field dispersion relations and Rabi frequencies. To quantify the role played by the monolayer graphene, we have defined two amplification coefficients of NFRHT. Finally, the contributions of thickness of the two different polar dielectrics to the strong coupling effects have been investigated. As a result, we demonstrate that the strong coupling effect we highlight is robust with respect to the mismatch between resonance frequencies, laying the foundation for an active control and enhancement of NFRHT between dissimilar materials.