大多數超穎介面元件設計僅考慮單元結構提供的相位延遲，然而，超穎單元主 要依賴不同的共振強度來實現相位延遲。這種操控方式必然會導致振幅在相同工作波 長下劇烈變化，從而使遠場波前的干涉狀況不符合預期，進而降低超穎元件的功能。 本文先以電磁學模擬方法，從反射光譜、相位變化等物理特性，由單元結構分析相位 分布，結合複數優化，設計並製造基於超穎介面之光束偏轉器。論文首先詳細探討在 不同奈米結構個數與異常反射角的情形下，光束偏轉器的特性。接著探討不同金屬奈 米結構厚度，對光束偏轉器的優化，及折射率與消光係數對於光束偏轉器的影響。最 後利用半導體製程製造基於相位優化與複數優化的光束偏轉器，並三種不同異常反射 角，分別為 10 度、 15 度、 20 度進行比較。研究結果發現，以複數優化的光束偏 轉器的與一般使用相位優化的光束偏轉器效能截然不同，對未來先進光電光學的研究、 發展與應用，提供了嶄新的奈米光學開發平台。

Most metasurface designs focus on phase delay provided by the unit structure, but they primarily rely on varying resonance intensities, leading to significant amplitude changes and performance degradation. In this work, we propose a complex optimization method to design and realize a metasurface-based beam deflector. We evaluate the beam deflector's performance with different numbers of nanostructure and deflection angles. Typical e-beam lithography process is used to fabricate beam deflectors optimized by the complex optimization method, comparing three deflection angles — 10, 15, and 20 degrees. By comparing with the phase-only design, the proposed complex optimization significantly improves performance, offering a new platform for advanced optoelectronics researches and applications.

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