グラフェンのサイズに依存したキャリアの移動性と極性に関する理論的予測
Meng-Qiu Long1, Ling Tang, Dong Wang
1Department of Chemistry, Tsinghua University, Beijing 100084, PR China.
Journal of the American Chemical Society
|November 21, 2009
まとめ
グラフェンリボンキャリアの移動性は,その幅に大きく左右されます. アームチェアグラフェンリボンには,ジグザグリボンとは異なり,特定の炭素構造に基づいて,電子と穴の移動性が交互に変化します.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- 計算物理学の物理
背景:
- グラフェンリボンは,ナノ電子機器のための有望な材料です.
- キャリアモビリティは,電子性能を決定する重要なパラメータです.
- 構造的変化がグラフェンの電子特性に及ぼす影響は,詳細な調査が必要である.
研究 の 目的:
- 椅子のグラフェンリボンにおける幅依存のキャリアモビリティを調査する.
- 椅子とジグザグ状のグラフェンリボンの電子輸送特性を比較する.
主な方法:
- 第一原理 密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.
- キャリア・モビリティ分析のための変形可能性理論.
主要な成果:
- アームチェアグラフェンリボンには,幅に依存する有意なキャリアモビリティがあります.
- 幅N = 3kの椅子リボンでは,電子の移動性は~10^6cm^2V^-1s^-1に達し,穴の移動性は~10^4cm^2V^-1s^-1である.
- N = 3k+1 または 3k+2 のアームチェアリボンでは,穴の可動性は 4-8 x 10^5 cm^2 V^-1 s^-1 で,電子の可動性は ~10^4 cm^2 V^-1 s^-1.
- この交互の移動行動は,ジグザグ状のグラフェンリボンでは観察されません.
結論:
- 座椅子のグラフェンリボンの幅は,そのキャリアモビリティを決定的に左右します.
- 座椅子のグラフェンリボン幅の調整は,それらの電子特性を制御するための経路を提供します.
- ジグザグ型のグラフェンリボンには,アームチェアと同じ幅に依存したモビリティの調節機能はありません.
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