Kane C L
Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Phys Rev Lett. 2003 Jun 6;90(22):226802. doi: 10.1103/PhysRevLett.90.226802. Epub 2003 Jun 2.
We study theoretically nonequilibrium noise in the fractional quantum Hall regime for an Aharonov-Bohm ring with a third contact in the middle of the ring. Because of their fractional statistics the tunneling of Laughlin quasiparticles between the inner and outer edges of the ring changes the effective Aharonov-Bohm flux experienced by quasiparticles going around the ring, leading to a change in the conductance across the ring. A small current in the middle contact, therefore, gives rise to fluctuations in the current flowing across the ring which resemble random telegraph noise. We analyze this noise using the chiral Luttinger liquid model. At low frequencies the telegraph noise varies inversely with the tunneling current and can be much larger than the shot noise. We propose that combining the Aharonov-Bohm effect with a noise measurement provides a direct method for observing fractional statistics.
我们从理论上研究了在分数量子霍尔体系中，一个在环中间有第三个接触点的阿哈罗诺夫 - 玻姆环中的非平衡噪声。由于其分数统计特性，劳克林准粒子在环的内边缘和外边缘之间的隧穿会改变围绕环运动的准粒子所经历的有效阿哈罗诺夫 - 玻姆通量，从而导致环上的电导发生变化。因此，中间接触点中的小电流会引起流过环的电流波动，这种波动类似于随机电报噪声。我们使用手征卢廷格液体模型来分析这种噪声。在低频时，电报噪声与隧穿电流成反比变化，并且可能比分立噪声大得多。我们提出，将阿哈罗诺夫 - 玻姆效应与噪声测量相结合，提供了一种观测分数统计的直接方法。
