Conductance fluctuations have been observed in macroscopic, quasi 3D PbTe wide quantum wells. A significant increase of the correlation field occurs in a temperature range from 40 mK to 1.2K. At the same time the fluctuation amplitude stays near e^2/h although the lateral sample size is two orders of magnitude larger than any typical length scale of diffusive electron transport. We interpret this behavior in terms of phasecoherent electrontransport, which takes advantage of a dramatic enhancement of the phasecoherence length of electrons in edgechannels and edge channel loops in the bulk region.
@article{arxiv.cond-mat/9707189,
title = {Phasecoherent Transport in PbTe Wide Parabolic Quantum Wells},
author = {J. Oswald and G. Span and A. Homer and G. Heigl and P. Ganitzer and D. K. Maude and J. C. Portal},
journal= {arXiv preprint arXiv:cond-mat/9707189},
year = {2008}
}
Comments
postscript file including 2 figs, 4 pages, paper presented at the 8th Int. Conf. on Narrow Gap Semiconductors, Shanghai April 21-24, 1997