Opt Express. 2023 Apr 10;31(8):13357-13365. doi: 10.1364/OE.484555.
The ability to manipulate thermal emission is paramount to the advancement of a wide variety of fields such as thermal management, sensing and thermophotovoltaics. In this work, we propose a microphotonic lens for achieving temperature-switchable self-focused thermal emission. By utilizing the coupling between isotropic localized resonators and the phase change properties of VO, we design a lens that selectively emits focused radiation at a wavelength of 4 µm when operated above the phase transition temperature of VO. Through direct calculation of thermal emission, we show that our lens produces a clear focal spot at the designed focal length above the phase transition of VO while emitting a maximum relative focal plane intensity that is 330 times lower below it. Such microphotonic devices capable of producing temperature-dependent focused thermal emission could benefit several applications such as thermal management and thermophotovoltaics while paving the way for next-generation contact-free sensing and on-chip infrared communication.
操控热辐射的能力对推动各种领域的发展至关重要，如热管理、传感和热光伏。在这项工作中，我们提出了一种微光子透镜，用于实现温度可切换的自聚焦热辐射。通过利用各向同性局域谐振器和 VO 的相变特性之间的耦合，我们设计了一种透镜，当 VO 的相变温度以上时，它会选择性地发射波长为 4μm 的聚焦辐射。通过对热辐射的直接计算，我们表明，当 VO 发生相变时，我们的透镜在设计的焦距处产生了清晰的焦点，而在其下方时，最大相对焦平面强度降低了 330 倍。这种能够产生随温度变化的聚焦热辐射的微光子器件可以应用于热管理和热光伏等领域，同时也为下一代非接触式传感和片上红外通信铺平了道路。
