弹道量子电线的四端电阻
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
概括
研究人员观察到弹道量子电线中的电阻消失,这挑战了标准的两探头测量. 这一发现凸显了散射在电阻现象中的重要性.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子运输是一种量子运输.
背景情况:
- 电阻源于电荷载体运动量因散射而放松.
- 在没有散射的完美导体中,电阻在理论上为零.
研究的目的:
- 为了研究单模弹道量子电线中的电阻.
- 为了比较四个终端的电阻测量与标准的两探头测量.
主要方法:
- 用于控制几何结构的GaAs/AlGaAs异构结构的裂边上利用表轴生长.
- 在弹道量子电线上使用弱入侵的电压探测器.
主要成果:
- 在弹道量子电线中观察到四个终端电阻的消失.
- 与标准的两探头电阻值约为13kΩ (h/2e2) 相比.
结论:
- 在弹道运输条件下,在干净的,一维的导体中展示了消失阻力.
- 这项研究提供了实验证据,证明当分散被最小化时,阻力不存在.
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