2025-06-20 ペンシルベニア州立大学 (PennState)
＜関連情報＞
- https://www.psu.edu/news/engineering/story/rewriting-scientific-law-unlock-potential-energy-sensing-and-more
- https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.135.016901
強い非反復熱放射の観察 Observation of Strong Nonreciprocal Thermal Emission
Zhenong Zhang, Alireza Kalantari Dehaghi, Pramit Ghosh, and Linxiao Zhu
Physical Review Letters Published: 30 June, 2025
DOI: https://doi.org/10.1103/PhysRevLett.135.016901
Abstract
The Kirchhoff’s law of thermal radiation stating the equivalence of emissivity and absorptivity at the same wavelength, angle, and polarization, has completely constrained emission and absorption processes. Achieving strong nonreciprocal emission points to fundamental advances for applications such as energy harvesting, heat transfer, and sensing, but strong nonreciprocal thermal emission has not been experimentally realized. Here, we observe strong nonreciprocal thermal emission using a custom-designed angle-resolved magnetic thermal emission spectroscopy and an epitaxially transferred gradient-doped metamaterial. We show that under magnetic field, the metamaterial strongly breaks Kirchhoff’s law, with a difference between emissivity and absorptivity at the same wavelength and angle reaching as high as 0.43. Significant nonreciprocal emission persists over broad spectral and angular ranges. The demonstration of strong nonreciprocal thermal emission and the approach can be useful for systematic exploration of nonreciprocal thermal photonics for thermal management, infrared camouflage, and energy conversion.
