利用带折叠诱导的近界模式来实现高度连贯的热排放
Kaili Sun1, Uriel Levy2, Zhanghua Han1
1Shandong Provincial Key Laboratory of Optics and Photonic Devices, Center of Light Manipulation and Applications, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
Nano letters
|January 2, 2024
概括
研究人员使用几何扰动和光学格子三倍化实现了中红外热辐射的高时间和空间连贯性. 这一突破为各种应用增强了连贯的热源.
科学领域:
- 光学和光子学 在光学和光子学.
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 高连贯度的热辐射对于实际应用至关重要,尽管通常不如激光相连贯.
- 之前的工作利用周期翻倍扰动来产生连贯的热辐射.
- 光学网格和Brillouin区域折叠是操纵光物质相互作用的关键现象.
研究的目的:
- 提出和研究具有同时具有高时间和空间连贯性的中红外热辐射.
- 为了探索几何扰动诱导的光学格子三倍化的效应.
- 为了利用Brillouin区域折叠来增强连贯性质.
主要方法:
- 利用几何扰动来诱导光学格子在三元格子中的三倍化.
- 利用Brillouin区域折叠效应来修改引导模式分散带.
- 分析了辐射波长和波向之间的关系.
- 时间连贯性 (带宽) 的实验性表征和空间连贯性长度的计算.
主要成果:
- 实现了具有高时间连贯性的中红外热辐射 (实验带宽~30 nm).
- 证明了超高的空间连贯性,计算的连贯度长度达到毫米尺度.
- 观察到引导模式分散带的的部分折叠到三元格中的 Γ 点.
- 发现特定的辐射波长对应于非常小的波导范围.
结论:
- 由几何扰动引起的光学格子三倍化和Brillouin区域折叠使中红外热发射器具有很高的时间和空间连贯性.
- 拟议的方法为超越传统限制的先进连贯热源提供了一条途径.
- 这些发现对需要精确控制热发射性能的应用具有重大意义.
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