シングル結晶リラクサーのスラッシュのような極性構造
Hiroyuki Takenaka1, Ilya Grinberg1,2, Shi Liu1
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Nature
|June 16, 2017
まとめ
リラクサー・フェロエレクトリックは 極性ナノ領域モデルではなく 多領域構造により ユニークな特性を有しています この発見は 複雑な行動や素材のデザインに 新たな洞察を与えてくれます
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- 超高ピエゾ電気係数と高伝導性といった ユニークな特性を有しています
- 確立された極性ナノ領域モデルは,リラクサーの行動を完全に説明できず,予測モデリングを妨げています.
- リラクサーの基本的な構造を理解することは,材料の設計と応用にとって極めて重要です.
研究 の 目的:
- リラクサー・フェロエレクトリックの基礎構造と,その異常特性との関係を解明する.
- リラクサー材料における空間と時間の偏振の相関を調査する.
- 極性ナノ領域の概念を超えたリラクサー行動のより正確なモデルを開発する.
主な方法:
- 試作品のPb(Mg1/3,Nb2/3) O3-PbTiO3リラクサータのシミュレーションを用いた.
- 材料内の構造,ドメインサイズ,および偏振相関を分析した.
- 実験的な分散分散データとシミュレーション結果を比較した.
主要な成果:
- リラックス剤の性質は,極小領域 (2〜10 nm) の多領域状態から生じ,非極性行列の概念に異議を唱える.
- リラクサーの極性構造と水のスラッシュ状態の間の類似性を特定した.
- 実験結果と一致する低角領域壁の高密度を示した.
結論:
- 極性ナノ領域ではなく,マルチドメイン状態がリラクサーのフェロ電気的振る舞いを支配する.
- この新しい構造的な理解は,以前は特徴づけられなかったリラクサースクラスを説明します.
- 適した性質を持つ新しいリラクサー材料の設計のための基礎を提供します.
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