バリスティック量子ワイヤの4端抵抗
R de Picciotto1, H L Stormer, L N Pfeiffer
1Bell-Labs, Lucent Technologies, Murray Hill, New Jersey 07974, USA. rd25@lucent.com
Nature
|May 3, 2001
まとめ
研究者らは弾道量子ワイヤの電気抵抗の消失を観察し,標準の2つの探査機の測定に挑戦しました. この発見は,電気抵抗現象における分散の重要性を強調しています.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 量子トランスポートとは
背景:
- 電気抵抗は,散乱による電荷キャリアのモメンタル・リラクゼーションから生じる.
- 散乱のない完璧な導体では,電気抵抗は理論的にはゼロです.
研究 の 目的:
- シングルモード弾道量子ワイヤの電気抵抗を調査する.
- 4端末の抵抗測定と標準の2端末の測定を比較する.
主な方法:
- 制御された幾何学のために,GaAs/AlGaAsの異質構造の割れた縁のエピタキシアル成長を利用した.
- 弾道量子ワイヤの弱侵入性電圧探査機を使用した.
主要な成果:
- 弾道量子ワイヤの4端の抵抗の消失を観測した.
- これを,約13 kΩ (h/2e2) の標準の2プローブレジスタンス値と比較した.
結論:
- 弾道輸送条件下でのクリーンで一次元な導体での消失抵抗を証明した.
- この研究は,散乱を最小限に抑えた場合,抵抗がないことを実証する実験的証拠を提供します.
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