热辐射的非对称方向控制
Jianbo Yu1, Rui Qin1, Yunbin Ying1
1State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
Advanced materials (Deerfield Beach, Fla.)
|July 21, 2023
概括
研究人员开发了一种使用元表面的定向热发射的新方法. 这种技术通过将热能引导到单个输出角度,从而实现高效的热传输,从而增强了热管理应用.
科学领域:
- 纳米光子学 纳米光子学
- 热力工程是热力工程中的一个.
- 在Metasurfaces上使用.
背景情况:
- 热排放的方向控制对于高效的热传输至关重要.
- 纳米光子技术提供了角选择性热发射,但由于对称带分散,在相互系统中实现不对称的发射是具有挑战性的.
研究的目的:
- 介绍一项在互换系统中实现非对称的定向热发射的总体策略.
- 为了展示一种用于高度定向的热发射的实验装置.
主要方法:
- 利用周期性扰动和破碎的镜像对称性来创建共振元格.
- 设计能够将共振衍射到对称输出角度的元表面,具有明显的效率.
主要成果:
- 在特定的观测角度 (+30°) 达到高发射率 (ɛ = 0.61).
- 在其他角度证明了低发射率 (ɛ < 0.3),证实了不对称的定向发射.
- 在中红外波长的实验验证.
结论:
- 拟议的策略允许在相互系统中实现非对称的定向热发射.
- 这一突破促进了超薄定制热源的开发.
- 对各种热工程应用具有重大潜在影响.
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