Engineering the Spectral and Spatial Dispersion of Thermal Emission via Polariton-Phonon Strong Coupling.
Engineering the Spectral and Spatial Dispersion of Thermal Emission via Polariton-Phonon Strong Coupling.
复制标题
通过极化子-声子强耦合设计热发射的光谱和空间色散。
DOI：
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
J. Caldwell
中科院分区：
文献类型：
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作者：
Guanyu Lu;C. Gubbin;J. Nolen;T. Folland;M. Tadjer;S. De Liberato;J. Caldwell
光学模式之间的强耦合可以实现到纳米光子设计中，以修改能量-动量色散关系。这种方法提供了潜在的途径调谐的热发射频率，线宽，偏振和空间相干性。在这里，我们采用传播和本地化的表面声子极化激元之间的三模强耦合，与区域折叠的纵向光学声子内的4 H-SiC纳米柱的周期性阵列。从实验和理论上探讨了三个极化激元分支之间的能量交换、模式演化和耦合强度。直接测量了强耦合对随角度变化的热发射的影响，与理论吻合得很好。我们证明了5倍的空间相干性和3倍的极化激元模式的品质因数增强的改善，这些混合模式也表现出混合的字符，可以使机会，实现电驱动发射。我们的研究结果表明，极化激元-声子强耦合使热发射器，这满足了一个简单的，重量轻，窄带，但明亮的发射器的主机的红外应用的要求。
Strong coupling between optical modes can be implemented into nanophotonic design to modify the energy-momentum dispersion relation. This approach offers potential avenues for tuning the thermal emission frequency, line width, polarization, and spatial coherence. Here, we employ three-mode strong coupling between propagating and localized surface phonon polaritons, with zone-folded longitudinal optic phonons within periodic arrays of 4H-SiC nanopillars. Energy exchange, mode evolution, and coupling strength between the three polariton branches are explored experimentally and theoretically. The influence of strong coupling upon the angle-dependent thermal emission was directly measured, providing excellent agreement with theory. We demonstrate a 5-fold improvement in the spatial coherence and 3-fold enhancement of the quality factor of the polaritonic modes, with these hybrid modes also exhibiting a mixed character that could enable opportunities to realize electrically driven emission. Our results show that polariton-phonon strong coupling enables thermal emitters, which meet the requirements for a host of IR applications in a simple, lightweight, narrow-band, and yet bright emitter.