本研究模擬一種二維平板型的超材料結構，藉以增加入射電磁波的吸收率，並將二維超材料吸收器推展成三維結構，亦進行分析比較。同時實作一個微波開口諧振環的超材料結構，並建立單極天線的量測環境，對微波超材料樣品進行量測驗證。本研究中模擬的平版型超材料吸收器是將金屬的陣列堆疊在一層介電質材料上，當電磁波入射至金屬，電磁波與金屬間產生特殊的電磁場共振效應，藉此提高電磁波吸收率。此吸收器在太赫茲波段達到極高吸收率，其操作頻率較窄，但相較於部分寬頻的吸收器可達到更高的吸收率。由於超材料本身微結構的大小在設計上須與入射電磁波波長相對應，本研究對此進行參數分析，藉以了解微結構尺寸大小造成操作頻率所對應吸收率曲線的變化情形。在實驗部分實際製作一種開口諧振環的微波超材料，藉由天線量測多種不同尺寸之微波開口諧振環的吸收現象，以比較量測出之透射係數的變化趨勢，來觀察微波超材料的電磁波吸收能力。

In this thesis, we present a highly efficient metamaterial absorber. This kind of metamaterial absorber can achieve nearly perfect absorption in terahertz regime. When incident light propagate through the metamaterial absorber, interaction between electromagnetic wave and the metamaterial structure cause a significant change in electromagnetic field resonance. Enhancing the local electric field resonance will result in better absorptions in corresponding frequency. Therefore, in this study, the metamaterial absorber is analysis by performing numerical simulation. Simulation shows that the proposed planar metamaterial absorber can achieve a high absorptivity over 99.9% at 70.73THz. And the average absorptivity in the range between 70THz to 80THz is over 79%.

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