分子シロキサンにおける極限伝導抑制
Haixing Li1, Marc H Garner2, Timothy A Su3
1Department of Applied Physics and Applied Mathematics, Columbia University , New York, New York 10027, United States.
Journal of the American Chemical Society
|July 14, 2017
まとめ
研究者はナノスケール電子機器のための二酸化シリコン分子ワイヤーを探しました これらのシロキサン分子は,分子隔離剤としての潜在能力を示す,長さに依存した有意な伝導性崩壊を示します.
科学分野:
- 材料科学
- ナノテクノロジー
- 固体物理学
背景:
- 伝統的な単一分子伝導性研究は,高伝導性分子ワイヤーを優先します.
- ナノスケールエレクトロニクスの進歩は,効果的な分子隔離器の開発を必要としています.
- 二酸化シリコンは固有の保温剤ですが,単一分子の性質は未熟です.
研究 の 目的:
- 二酸化シリコンベースの分子ワイヤの単分子導電性を調査する.
- シロキサン分子の長さに依存する導電性分解を決定する.
- 電子機器における分子隔離剤としてのシロキサンの可能性を評価する.
主な方法:
- シリコン-酸素 (Si-O) リピートユニットから成る分子ワイヤの合成.
- スキャニングトンネル顕微鏡ベースの断路技術を使用して単一分子導電性を測定する.
- 単一分子交差点伝送と複雑な帯域構造の計算を含む計算分析.
主要な成果:
- シロキサン分子は,比較可能な長さのアルカンよりも低い伝導性を示した.
- 合成された分子は,これまでに観測された最も顕著な長さ依存の伝導性崩壊を示した.
- 計算により,SiOボンドの本質的な性質が,導電性の減少の原因であることが確認された.
結論:
- シロキサン分子は分子隔離に適したユニークな性質を持っています.
- ナノスケール電子断熱器におけるそれらの潜在的応用を強調している.
- この研究は,高度な電子部品の分子断熱器の設計と利用のための新しい道を開きます.
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