Near-Field Radiative Heat Transfer Between Mie Resonance-Based Metamaterials Made of Coated Nonmagnetic Particles

Abstract Near-field radiative heat transfer between Mie resonance-based metamaterials composed of SiC/d-Si (silicon carbide and doped silicon) core/shell particles immersed in aligned nematic liquid crystals are numerically investigated. The metamaterials composed of core/shell particles exhibit superior performances of enhanced heat transfer and obvious modulation effect when compared to that without shell. The underlying mechanism can be explained that the excitation of Fröhlich mode and epsilon-near-zero (ENZ) resonances both contribute to the total heat flux. Modulation of near-field radiative heat transfer can be realized with the host material of aligned nematic liquid crystals. The largest modulation ratio could be achieved as high as 0.45 for metamaterials composed of core/shell SiC/d-Si particles, and the corresponding heat flux is higher than other similar materials such as LiTaO3/GaSb and Ge/LiTaO3. While with the same volume filling fraction, the modulation ratio of that composed of SiC particles is only 0.2. We show that the core/shell nanoparticles dispersed liquid crystals (NDLCs) have a great potential in enhancing the near-field radiative heat transfer in both the p and s polarizations with the radii of 0.65 μm, and Mie-metamaterials are shown for the first time to modulate heat flux within sub-milliseconds.

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Magnetic-field control of near-field radiative heat transfer by liquid crystals-based magneto-optical metamaterials

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac1624 ◽

2021 ◽

Author(s):

Lu Lu ◽

Kun Zhou ◽

Bo Zhang ◽

Bowen Li ◽

Zixue Luo ◽

...

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Liquid Crystals ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Near Field ◽

Optical Metamaterials ◽

Field Control

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Ultrasensitive Bimaterial Cantilevers Optimized for Nanowire Heat Conduction Measurement

ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2012-75169 ◽

2012 ◽

Author(s):

Carlo Canetta ◽

Ning Gu ◽

Arvind Narayanaswamy

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Heat Conduction ◽

Silicon Nitride ◽

Flat Plate ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Near Field ◽

Aluminum Coating ◽

Thermal Sensors

We have developed a microcantilever-based technique for measurement of heat conduction through individual nanowires. We fabricated silicon nitride cantilevers with nominal dimensions of length 100 μm, width 2–6 μm, and thickness 130 nm. Cantilever chips are designed with multiple cantilevers spaced at varying distances. With a reflective aluminum coating of optimized thickness, these bimaterial cantilevers can be used as ultrasensitive thermal sensors capable of measuring very small heat flux through a nanostructure fixed between two cantilevers. The ultrasensitive bimaterial cantilevers designed in this work are not limited to heat conduction measurements, but will also be useful for measuring near-field radiative heat transfer between a sphere, attached to the tip of the cantilever, and a flat plate.

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Near-Field Radiative Heat Transfer Between Two α-MoO3 Biaxial Crystals

Journal of Heat Transfer ◽

10.1115/1.4046968 ◽

2020 ◽

Vol 142 (7) ◽

Cited By ~ 1

Author(s):

Xiaohu Wu ◽

Ceji Fu ◽

Zhuomin M. Zhang

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Hexagonal Boron Nitride ◽

Near Field ◽

Radiative Heat Flux ◽

Relative Rotation ◽

Maximum Heat ◽

Phonon Polaritons

Abstract The near-field radiative heat transfer (NFRHT) between two semi-infinite α-MoO3 biaxial crystals is investigated numerically based on the fluctuation–dissipation theorem combined with the modified 4 × 4 transfer matrix method in this paper. In the calculations, the near-field radiative heat flux (NFRHF) along each of the crystalline directions of α-MoO3 is obtained by controlling the orientation of the biaxial crystals. The results show that much larger heat flux than that between two semi-infinite hexagonal boron nitride can be achieved in the near-field regime, and the maximum heat flux is along the [001] crystalline direction. The mechanisms for the large radiative heat flux are explained as due to existence of hyperbolic phonon polaritons (HPPs) inside α-MoO3 and excitation of hyperbolic surface phonon polaritons (HSPhPs) at the vacuum/α-MoO3 interfaces. The effect of relative rotation between the emitter and the receiver on the heat flux is also investigated. It is found that the heat flux varies significantly with the relative rotation angle. The modulation contrast can be as large as two when the heat flux is along the [010] direction. We attribute the large modulation contrast mainly to the misalignment of HSPhPs and HPPs between the emitter and the receiver. Hence, the results obtained in this work may provide a promising way for manipulating near-field radiative heat transfer between anisotropic materials.

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Near-Field Radiative Heat Transfer Between Materials With Dielectric Coatings

2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems ◽

10.1115/micronano2008-70279 ◽

2008 ◽

Author(s):

Ceji Fu ◽

Wenchang Tan

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Coating Thickness ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Near Field ◽

Dielectric Coating ◽

Radiative Heat Flux ◽

Surface Polaritons ◽

Dielectric Coatings

Radiative heat transfer between materials with dielectric coatings is numerically studied based on the fluctuational electrodynamics and the fluctuation-dissipation theorem. The results show that whereas a dielectric coating (SiC) enhances the far-field radiative heat transfer between two bulk metals, it will suppress the radiative heat transfer in the near-field and the suppression is only for the s-wave contribution. The total radiative heat flux continuously decreases as the coating thickness increases up to 1 μm. A further increase in the coating thickness will cause the total radiative heat flux to increase slightly before it saturates. In addition, a much smaller coating thickness than the coating’s skin depth is enough to significantly change the total radiative heat flux in the near-field region. On the contrary, a thin dielectric coating that supports surface polaritons can greatly enhance the radiative heat transfer between a metal and a dielectric in the case that the coating is on the metal. The large enhancement is due to surface polaritons excited on the two surfaces of the air gap boundaries.

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