超材料是一種人工材料，其電磁性質在不同頻率的電磁波影響下，可呈現出迥異、甚至自然物質所沒有之電磁特性。在過去的二十年內，各式各樣的超材料應用被陸續的提出，例如：負折射率材料、隱形斗篷、完美吸收體、人工偏極板與波板、光減速系統。事實上，過去大多數的超材料的研究與應用頻段都是在微波頻段、兆赫頻段和紅外光頻段，而且可以被應用於通訊系統、電子系統和生物感測上。但是超材料位於光學頻段的研究卻鮮少被提及，因為其製造難度較高且電磁模擬常受制於電腦能力之不足。
超材料應用的其中一種是人工光學偏極板，其研究涵蓋了微波頻段到可見光頻段，此應用被稱作旋光超材料且可被製作成立體式結構或平面型結構；平面型結構則被稱為平面型旋光超材料。近年來，科學家對位於光學頻段的平面型旋光超材料產生了研究興趣，因為它具有能被改良或被發展出嶄新光學性質的潛力。雖然旋光性超材料的組成物質並不具有任何的光學活性，但研究顯示旋光性仍舊可以藉由特殊設計的圖案產生。為了達成更強的光學活性或是發展出特殊光學性質，科學家研究了不同的材料與圖形結構，例如十字形、卍字形、絲帶形、隙環共振器形與奈米孔洞等。
在此研究中，我們選擇了卍字形作為骨架，並設計出一些類卍字形且四軸對稱的圖案。這些複雜圖案在一階繞射中展現了比以往的簡單卍字形更為優異的光學性質。我們從電腦模擬開始，配合奈米製造技術：電子束微影，最後利用偏極計量測其位於可見光頻段的極化狀態改變。實驗結果顯示，這些複雜的類卍字形結構擁有非常大的極化旋轉角，且線寬、金屬膜厚度和圖形對於平面型旋光超材料的表現有相當重要的影響力。在研究之中，最佳的旋轉角達到了73°，對應之旋轉能力為1.33×106 deg/mm；此結果分別是過去類似研究的5倍與12倍。最後，透過電腦模擬，我們利用電場和磁矩分布來解釋可能的新反應機制。

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