Broadband directional control of thermal emission

@article{Xu2021BroadbandDC,
  title={Broadband directional control of thermal emission},
  author={Jin Xu and Jyotirmoy Mandal and Aaswath Pattabhi Raman},
  journal={Science},
  year={2021},
  volume={372},
  pages={393 - 397}
}
Broadband thermal beaming Thermal radiation emits over a wide range of wavelengths and over a wide range of angles. Xu et al. constructed a material that allows a range of wavelengths to emit over a much narrower range of angles. This property allowed the authors to beam thermal energy preferentially in one direction. The strategy requires carefully exploiting stacks of epsilon-near-zero films in which the angular range of thermal emission is controlled by the film thickness. This design could… 
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