分子連鎖トンネリングの交差点

Kung-Ching Liao¹, Liang-Yan Hsu², Carleen M Bowers¹

¹†Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|April 15, 2015

まとめ

分子結合における電荷輸送は,量子力学的に振る舞う. 連続接続された絶縁分子単位を通るトンネリング電流の密度は,修正されたシモンズ方程式に従って,その順序から独立しています.

科学分野:

分子電子学の量子現象
自己組み立てモノレイヤーの充電輸送メカニズムを充電します.

背景:

古典的な回路法則は,分子交差点における電荷輸送を不十分に記述している.
自己組み立てモノレイヤー (SAM) は,量子トンネリングの研究のためのプラットフォームを提供します.

研究の目的:

異なる絶縁分子単位から成る連続トンネリングの交差点におけるトンネリング電流密度を調査する.
負荷輸送率に対する分子単位順序の影響を分析する.

主な方法:

Ag(TS) /O2C-R1-R2-H//Ga2O3/EGaInの接着点の製造には,様々な断熱装置 (R1,R2) が使用されています.
修正されたシモンズ方程式を用いた電流密度 (J(V)) の分析: J(V) = J0(V) exp(-β1d1 - β2d2).
Ag/O2Cインターフェース経由で分子軌道を解離し,トンネリング貢献を隔離する.

主要な成果:

荷重輸送率は,SAM内の分子単位 (R1とR2) の順序とは無関係であった.
R1とR2の電子構造は,トンネルの速度を決定したが,その順番は決定しなかった.
電気ポテンシャルモデルでは,R1とR2がバリアの高さに独立して貢献していることが示された.

結論:

連続的に接続された絶縁ユニットを持つ分子結合は,量子トンネリングの振る舞いを示します.
絶縁ユニットの順番は,加熱バリアモデルを支える,全体的な負荷輸送に影響を与えない.
この研究は,分子電子機器における電荷輸送の制御に関する洞察を提供します.

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