A confinement‐induced nonlocal electromagnetic response model is applied to study radiative heat transfer processes in transdimensional plasmonic film systems. The results are compared to the standard local Drude model routinely used in plasmonics. The former predicts greater Woltersdorff length in the far‐field and larger film thicknesses at which heat transfer is dominated by surface plasmons in the near‐field, than the latter. The 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 in order 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 with thin and ultrathin metallic films and coatings.
- PAR ID:
- 10477054
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review Letters
- Volume:
- 131
- Issue:
- 8
- ISSN:
- 0031-9007
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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