宽带非互惠的热发射率和吸收率
Komron J Shayegan1,2, Jae S Hwang3, Bo Zhao4
1Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA.
Light, science & applications
|July 24, 2024
概括
研究人员使用梯度epsilon-near-zero InAs层实现了宽带非互惠的热发射率和吸收率. 这一突破使得在能源应用中能够加强对红外光谱中的热辐射的控制.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 光学是什么?光学是什么?光学是什么?
背景情况:
- 基尔霍夫的热辐射定律指出,一个处于热平衡的物体的吸收率等于发射率.
- 违反基尔霍夫定律对于推进光子能量转换和辐射冷却技术至关重要.
- 以前对光谱定向发射率和吸收率不平等的证明仅限于狭窄的共振或非红外波长.
研究的目的:
- 为了证明宽带非互惠的热发射率和吸收率.
- 为了实现对不平等的光谱定向吸收率和辐射率的广泛光谱范围的控制.
- 探索光子能量转换和辐射冷却中的实际应用潜力.
主要方法:
- 使用的梯度是epsilon-near-zero印度甲 (InAs) 层,其子波长厚度为50nm和150nm.
- 应用外部磁场来诱导非互惠.
- 在特定的红外光谱范围内 (12.5-16微米) 测量热发射率和吸收率.
主要成果:
- 证明了宽带非互惠的热发射率和吸收率.
- 在12.5-16微米光谱范围内实现了效果,并与红外透明窗相重叠.
- 在中等磁场强度 (1特斯拉) 观察到这种现象.
结论:
- 该研究成功地证明了宽带非互惠热辐射,这与之前的窄带或非红外示范相比是一个显著的进步.
- 使用梯度epsilon-near-zero InAs层为需要量身定制的热辐射特性的实际应用提供了一个有希望的途径.
- 这项工作为利用辐射传热的设备提高性能铺平了道路,例如先进的能量转换器和冷却系统.
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