All open systems that exchange energy with their environment are non‐Hermitian. Thermal emitters are open systems that can benefit from the rich set of physical phenomena enabled by their non‐Hermitian description. Using phase, symmetry, chirality, and topology, thermal radiation from hot surfaces can be unconventionally engineered to generate light with new states. Such thermal emitters are necessary for a wide variety of applications in sensing and energy conversion. Here, a non‐Hermitian selective thermal emitter is experimentally demonstrated, which exhibits passive
Thermal emission is the radiation of electromagnetic waves from hot objects. The promise of thermal‐emission engineering for applications in energy harvesting, radiative cooling, and thermal camouflage has recently led to renewed research interest in this topic. However, accurate and precise measurements of thermal emission in a laboratory setting can be challenging in part due to the presence of background emission from the surrounding environment and the measurement instrument itself. This problem is especially acute for thermal emitters that have unconventional temperature dependence, operate at low temperatures, or are out of equilibrium. In this paper, general procedures are described, recommended, and demonstrated for thermal‐emission measurements that can accommodate such unconventional thermal emitters.
more » « less- Award ID(s):
- 1750341
- PAR ID:
- 10456146
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Laser & Photonics Reviews
- Volume:
- 14
- Issue:
- 8
- ISSN:
- 1863-8880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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