非対称な自立の2D光学結晶膜とそのジャヌス粒子
Jian-Tao Zhang1, Xing Chao, Sanford A Asher
1Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, USA.
Journal of the American Chemical Society
|July 23, 2013
まとめ
研究者らは,ポリシュチレン粒子とTEOSを使って,大きく,薄く,自立した2Dフォトニック結晶を作成しました. この方法により,光を微分する光子結晶膜とエッチング後の新しいジャヌス粒子が生成されます.
科学分野:
- マテリアルサイエンス 材料科学
- ナノテクノロジー ナノテクノロジー
- オプティクスは光学です.
背景:
- 二次元 (2D) フォトニック結晶は,独特の光散射特性を持っています.
- 大面積のフリースタンド光子結晶の製造は依然として課題です.
研究 の 目的:
- 大面積,非対称,自立した2次元光学結晶を製造する方法を開発する.
- これらの光子結晶の構造的変化と,その結果生じる性質を調査する.
主な方法:
- 針の先の流れ法を用いて,空気/水のインターフェイスで密集したポリシュチレン (PS) 粒子のモノレイヤを作成しました.
- テトラエチルオーソシリケート (TEOS) を適用して薄い層を形成し,蒸発時に粒子の半球融合を誘導します.
- 構造変更と粒子の分離のために,反応性イオンエッチング (RIE) と機械摩擦を使用しています.
主要な成果:
- 効率的な光 difraktion を有する,大きな面積,薄い,非対称なフリースタンドの2Dフォトニッククリスタルフィルムを成功裏に製造しました.
- フィルムは,溶けた半球面と平らなシート面を持つユニークな構造を示しています.
- RIEは,新しい,粗い2D配列と花のような配列を生成し,磨き後のジャヌス粒子を導いた.
結論:
- 開発された方法は,高度な2Dフォトニック結晶構造のスケーラブルな製造を可能にします.
- その結果生じる非対称フィルムと派生したジャヌス粒子は,光学および材料の応用のための新しい可能性を提示します.
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