グラフェンの粘性電子の逆流によって引き起こされる負の局所抵抗

D A Bandurin¹, I Torre², R Krishna Kumar³

¹School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK.

Science (New York, N.Y.)

|February 26, 2016

まとめ

科学者は電子がグラフェンの粘性液として渦巻きを形成し水力学的な現象を呈することを観察しましたこの発見は,高度な材料における電子水力学の研究の新たな道を開きます.

科学分野:

凝縮物質物理学
材料科学
量子電子

背景:

グラフェンは,弱い電子-フォノン散乱と頻繁な電子-電子衝突を持つユニークな電子システムを持っています.
液体窒素の温度以上では,グラフェン電子は局所的な均衡を達成し,粘着性のある液体のように振る舞い,水力学的な現象を示します.

研究の目的:

ドーピングされたグラフェンの電子の水力学的輸送体制の強力な証拠を提供するためです.
グラフェンの電子液体の粘性特性を調べる

主な方法:

電流注入コンタクト近くのドープされたグラフェンの異常な電圧低下の実験観察.
電子の流れパターンの分析,特にサブマイクロメートルのサイズの渦の形成.

主要な成果:

電子の渦が形成されていることを示す異常な (負の) 電圧低下が検出されました.
グラフェンの電子液の粘度は約0.1m2/sで,蜂蜜よりも大幅に高かった.
結果は多体理論の予測と一致しています

結論:

この研究は,グラフェンの電子水力学に関する説得力のある証拠を提供します.
グラフェンの電子液体は測定可能な粘度を示し,これらの現象を研究するためのプラットフォームを提供します.
この研究は,高品質のグラフェンサンプルでの電子水力学の研究の可能性を示しています.

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