極化調節されたスメクティック液晶相
D A Coleman1, J Fernsler, N Chattham
1Department of Physics and Ferroelectric Liquid Crystal Materials Research Center, University of Colorado, Boulder, CO80309 - 0390, USA.
Science (New York, N.Y.)
|August 30, 2003
まとめ
研究者らは,内なる不満を克服する流動的極性スメクティック液晶を発見した. これらの材料は,安定した,局所的に広がった極化パターンを示し,ユニークなストライプとフィラメント構造を形成します.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- ソフトマター物理学 ソフトマター物理学
背景:
- 均一な極化場を持つ極性有序の材料は,非均一な局所的極化に対する対称性の要件のために,内部的な挫折を経験します.
- 欠陥は通常,局所的偏振スプレーを達成するために必要ですが,従来の鉄電結晶と液晶ではしばしば不安定であり,グローバルな挫折につながります.
研究 の 目的:
- 安定した,非均一な極化場を示す新種の流動的極性スメクティック液晶を報告する.
- これらの材料における局所的に広がる極化パターンの形成と特徴を調査する.
主な方法:
- 周期的な超分子スケールの極化変調のストライプを示す流体極性スメクティック液晶の調査.
- 極化ストライプと層の波動波の結合の分析.
- 地元のキラリティと極域の組織を特徴づける.
主要な成果:
- 流動的極性スメクティック液晶のクラスは,局所的極化スプレーが安定し,一般的であると特定されました.
- これらの材料は,層の波動波と結合した周期的偏振変調のストライプを表示します.
- 極域は局所的なキラリティを示し,手性と極性の交替パターンに編成され,多様なフィラメントと平面構造を形成します.
結論:
- 流動的極性スメクティック液晶は,安定した,調節された極化場を形成することによって,極性物質の典型的な内部挫折を克服することができます.
- 観測された流体層の波紋は,複雑で組織的な構造の形成を促進し,材料設計のための新しい道を開きます.
- これらの発見は,柔らかい物質のシステムにおける非均一な極化を達成するための新しいパラダイムを導入します.
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