Peled E, Shahar D, Chen Y, Sivco D L, Cho A Y
Department of Condensed Matter Physics, Weizmann Institute, Rehovot 76100, Israel.
Phys Rev Lett. 2003 Jun 20;90(24):246802. doi: 10.1103/PhysRevLett.90.246802. Epub 2003 Jun 18.
We present an experimental study of mesoscopic, two-dimensional electronic systems at high magnetic fields. Our samples, prepared from a low-mobility InGaAs/InAlAs wafer, exhibit reproducible, sample specific, resistance fluctuations. Focusing on the lowest Landau level, we find that, while the diagonal resistivity displays strong fluctuations, the Hall resistivity is free of fluctuations and remains quantized at its nu=1 value, h/e(2). This is true also in the insulating phase that terminates the quantum Hall series. These results extend the validity of the semicircle law of conductivity in the quantum Hall effect to the mesoscopic regime.
我们展示了在高磁场下对介观二维电子系统的实验研究。我们的样品由低迁移率的 InGaAs/InAlAs 晶圆制备而成，表现出可重复的、特定于样品的电阻波动。聚焦于最低朗道能级，我们发现，虽然对角电阻率显示出强烈波动，但霍尔电阻率没有波动，并且在其 ν = 1 值 h/e² 处保持量子化。这在终止量子霍尔序列的绝缘相中也是如此。这些结果将量子霍尔效应中电导率半圆定律的有效性扩展到了介观领域。
