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Abstract With chemical stability under high temperatures, dielectric materials can be idealized thermal emitters for different energy applications. However, dielectric materials do not support surface waves at near-infrared ranges for longer-distance thermal photon tunneling, which limits their applications in near-field thermal radiation. It is demonstrated in this study that thermal field amplification at near-infrared wavelengths at dielectric surfaces could be achieved through asymmetric Fabry–Perot resonance with anti-reflection coatings or 1D photonic crystal type structures. ⩾100 nm near-infrared thermal photon tunneling can be achieved when these thin film structures are added to the emitter and the collector surfaces. Among these two thin film structures, 1D photonic crystal type periodic structures constructed with the same high refractive index material as the emitter/collector material allow near-field thermal photon tunneling at large parallel wavenumbers. Moreover, the field amplification can be increased by adding more 1D photonic crystal layers to achieve even longer distances near field thermal photon tunneling.
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A mathematical model for thermal radiation between non-continuous periodic structures and its application in near-field radiation between split ring resonators
Abstract A mathematical model has been developed to study far-field and near-field thermal emission from non-continuous periodic structures. Non-continuous periodic structures with appropriate geometries and materials can support electric or magnetic resonance, idealized for designing far-field perfect absorbers and near-field emitters/absorbers supporting long-distance photon tunneling. However, these structures do not have close format dyadic Green’s function to describe the thermal radiation from randomly fluctuating thermal current. Thus, simulating the near-field radiation spectrum between emitters and collectors patterned with these non-continuous periodic structures is challenging. Though finding eigenmodes of white-noise-like fluctuating thermal current satisfying this specific geometry, we extended the Wiener-Chaotic expansion type of near-field simulation to study far-field and near-field thermal emission from non-continuous periodic structures. After verifications with reference cases, the new mathematical method is applied to study photon tunneling between the emitter and the collector patterned with single-ring split ring resonance rings (SRR) supporting magnetic field resonance. It is observed from the new mathematical model that long photon tunneling can occur under such a configuration through magnetic field coupling between the emitter and collector at the magnetic resonance frequency of SRRs.
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- Award ID(s):
- 2117953
- PAR ID:
- 10572147
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics D: Applied Physics
- Volume:
- 58
- Issue:
- 13
- ISSN:
- 0022-3727
- Format(s):
- Medium: X Size: Article No. 135506
- Size(s):
- Article No. 135506
- Sponsoring Org:
- National Science Foundation
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