Regulation of thermal radiation plays a significant role in many applications, including radiative cooling, infrared camouflage and so on. In this work, a narrow-band VO-based thermal emitter composed of Ti/VO/Ti grating is first proposed to switch thermal radiation. Due to the exaction of MPs, the emitter yields a high and direction-insensitive emission peak in the mid-infrared when VO is at insulating state while exhibits low emission when VO is at metallic state, and thus realizes the "on" and "off" modes of thermal radiation before and after phase transition of VO. Furthermore, we construct a composite MIM grating structure by stacking four periods of single MIM gratings having different ridge widths, so as to realize broad-band switchable thermal radiation. Results show that, the decrease rate of emitted energy for the narrow-band emitter reaches 66% while reduces to 47% for the broad-band emitter. Furthermore, a larger contrast ratio of energy can be obtained with thermal hysteresis compared with the case without hysteresis. This work may facilitate applications in active infrared camouflage and other emission engineering fields.

中文翻译：

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使用磁极化子的基于 VO2 的可切换热发射器

热辐射调节在许多应用中发挥着重要作用，包括辐射冷却、红外伪装等。在这项工作中，首先提出了一种由 Ti/VO/Ti 光栅组成的窄带 VO 基热发射器来切换热辐射。由于MPs的严格要求，当VO处于绝缘态时，发射器在中红外区域产生高且方向不敏感的发射峰，而当VO处于金属态时则表现出低发射峰，从而实现“开”和“关” “VO 相变前后的热辐射模式。此外，我们通过堆叠四个周期具有不同脊宽的单个MIM光栅来构造复合MIM光栅结构，从而实现宽带可切换的热辐射。结果表明，窄带发射器的发射能量下降率达到66%，而宽带发射器的发射能量下降率为47%。此外，与没有磁滞的情况相比，具有热磁滞的情况可以获得更大的能量对比度。这项工作可能有助于主动红外伪装和其他发射工程领域的应用。