極流体ヘリコニックフェロ電気ネマティック相における自発的なキラル対称性破裂

Jakub Karcz¹, Jakub Herman¹, Natan Rychłowicz¹

¹Faculty of Advanced Technology and Chemistry, Military University of Technology, Warsaw, Poland.

Science (New York, N.Y.)

|June 6, 2024

まとめ

研究者らは,自発的なキラル構造と電鉄ネマティック液晶相における極性秩序を観察した. この新しいキラル・フェロ電気ネマティック・フェーズには,温度や電気場によって調整可能な光の反射特性があります.

科学分野:

材料科学
凝縮物質物理学
柔らかい物質の物理

背景:

流体の中で自発的な鏡の対称性破裂と極性秩序は珍しい.
これらの現象はネマティック液晶では別々に観察されているが,同時に観察されていない.
アキラル分子は典型的にはキラル構造を形成しない.

研究の目的:

流体における自発的なキラリティと極性秩序の同時観測を報告する.
鉄電気ネマティックフェーズにおける新しいヘリコニカル配列を調査する.
このキラル・フェロエレクトリック・ネマティック・フェーズの性質と仕組みを調査する.

主な方法:

超分子構造を形成するためにアキラルの構成要素を利用した
鉄電気ネマティック液晶相を調査した.
ヘリコニック構造とその光学特性を特徴付けました.

主要な成果:

アキラル分子は,鉄電気ネマティックフェーズ内でヘリコニカル構造に自己組み立てました.
結果的に発生した相は,自発的な極性秩序とキラリティを示した.
ヘリコニカル構造のピッチは可視光スペクトルにあり,選択的反射を可能にしました.
選択的反射は温度や弱い電場によって制御可能であった.

結論:

アキラル分子は,フェロ電気ネマティック液晶相において,同時に極性およびキラル構造を形成することができる.
このキラル・フェロエレクトリック・ネマティック・フェーズは調節可能な光学特性を備えています
この現象の鍵となるのは,非対線二極方向を誘導する電気相互作用である.

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