クラシックな結晶薄膜系における準結晶構造の形成
Stefan Förster1, Klaus Meinel, René Hammer
1Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, 06120 Halle, Germany.
Nature
|October 11, 2013
まとめ
研究者らは,新しいタイプの酸化準結晶を発見し,プラチナ基板に12倍対称性の2D構造を形成しました. この発見は準結晶の応用を拡大し,インターフェース駆動の無周期的相形成を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- クリスタログラフィーです.
- 表面科学とは,地表科学である.
背景:
- 準結晶は,秩序ある,しかし無周期的な構造であり,最初は金属間系で見つかった.
- 最近の発見には,コロイドおよび超分子化学における"柔らかい"準結晶が含まれています.
- この研究は,準結晶の観測を酸化物材料に拡張することに焦点を当てています.
研究 の 目的:
- 二次元準結晶として成長する無周期性酸化物の形成を報告する.
- 準結晶構造のインターフェース主導の形成を調査する.
- 材料科学とエピタキシにおけるこれらの構造の潜在能力を探求する.
主な方法:
- プラチナ (Pt(111)) 基板上のバリウムチタナート (BaTiO3) のエピタキシアル成長.
- インターフェースの高温構造分析.
- その結果生じる準結晶相の特徴とその対称性.
主要な成果:
- バリウムチタナート (BaTiO3) は,Pt(111) 基板に12倍対称性の高温,インターフェース駆動構造を形成しました.
- 構造は,スタンプフリ-ゲーラー・タイリングと一致する十二角対称性を表しています.
- 準結晶の構成要素には,0.69nmの基本長度スケールが観測されました.
結論:
- この研究は,超薄酸化物準結晶のインターフェース駆動による形成を実証しています.
- 周期性物質の間の界面における挫折は,非周期性準結晶相を誘発する可能性があります.
- これらの準結晶は,エピタキシにおける格子不一致の管理のためのバッファー層として機能する可能性があります.
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