局所化とその欠如:ポリマーの伝導性のための新しい金属状態

P Phillips, H L Wu

Science (New York, N.Y.)

|June 28, 1991

まとめ

乱雑な1次元のシステムは,長距離輸送を示し,これまでの固体物理学の見解に異議を唱えます. ランダム・ダイマー・モデルは,ポリマーにおける弾性粒子の動きを可能にする伝導状態を明らかにする.

科学分野:

固体物理学固体物理学とは
凝縮物質理論は,凝縮物質理論である.
マテリアルサイエンス材料科学

背景:

一次元のシステムの乱れは,伝統的に長距離輸送を妨げています.
最近の理論モデルは,この既成概念に異議を唱えている.
乱雑な物質の輸送を理解することは,電子アプリケーションにとって非常に重要です.

研究の目的:

遠距離輸送を1次元で説明するランダムダイマーモデルの有効性を調査する.
導電性ポリマーの断熱器-金属移行にこのモデルの適用性を調査する.
特定のポリマー系における導電性状態の存在を分析する.

主な方法:

ランダムダイマーモデルの導入と分析.
線形連鎖における格子部位のペアにランダムな部位エネルギーを割り当てる.
計算をポリアニニリンとポリパラフェニレンに適用する.

主要な成果:

ランダム・ダイマー・モデルは,弾道性に近い粒子輸送を可能にする伝導状態を予測する.
ポリアニリンの場合,これらの伝導状態は,金属体制のフェルミレベルと一致します.
ポリパラフェニレンに関する同様の分析は,バンドエッジ近くの導電状態を示しています.

結論:

混乱は,一次元システムにおける長距離輸送を必ずしも防ぐわけではない.
ランダムダイマーモデルは,導電性ポリマーにおける断熱器-金属移行を理解するための実行可能な枠組みを提供します.
このモデルの影響は,重量ドーピングされたポリアセチレンなどの他のポリマーにも及ぶ.

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