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Abstract 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.
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Nonlocal Near-Field Radiative Heat Transfer by Transdimensional Plasmonics
Using transdimensional plasmonic materials (TDPM) within the framework of fluctuational electrodynamics, we demonstrate nonlocality in dielectric response alters near-field heat transfer at gap sizes on the order of hundreds of nanometers. Our theoretical study reveals that, opposite to the local model prediction, propagating waves can transport energy through the TDPM. However, energy transport by polaritons at shorter separations is reduced due to the metallic response of TDPM stronger than that predicted by the local model. Our experiments conducted for a configuration with a silica sphere and a doped silicon plate coated with an ultrathin layer of platinum as the TDPM show good agreement with the nonlocal near-field radiation theory. Our experimental work in conjunction with the nonlocal theory has important implications in thermophotovoltaic energy conversion, thermal management applications with metal coatings, and quantum-optical structures.
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- 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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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevLett.131.086901
