Far- and near-field heat transfer in transdimensional plasmonic film systems*

Radiative heat transfer in transdimensional plasmonic film systems is analyzed using the confinement-induced nonlocal electromagnetic response model built on the Keldysh-Rytova electron interaction potential [1]. Results are compared to the local Drude model routinely used in plasmonics. The former predicts greater Woltersdorff length in the far-field and larger film thickness at which heat transfer is dominated by surface plasmons in the near-field, than the latter. Analysis performed suggests that the theoretical treatment and experimental data interpretation for thin and ultrathin metallic film systems must incorporate the confinement-induced nonlocal effect to provide reliable results in radiative heat transfer studies. The fact that the enhanced far- and near-field radiative heat transfer occurs for much thicker films than the standard Drude model predicts is crucial for thermal management applications and in general for the development of new quantum photonics materials based on ultrathin metallic films and metasurfaces of controlled thickness. The latest experiments to confirm this fact will also be reported [2]. – [1] S.-A.Biehs and I.V.Bondarev, Adv. Optical Mater. 11, 2202712 (2023); [2] H.Salihoglu, et al., Phys. Rev. Lett. 131, 086901 (2023).