Phasecoherent Transport in PbTe Wide Parabolic Quantum Wells

TL;DR

This paper investigates phasecoherent electron transport in macroscopic PbTe wide quantum wells, revealing enhanced phase coherence and conductance fluctuations at low temperatures, with implications for understanding quantum transport in large-scale systems.

Contribution

It demonstrates phasecoherent transport in macroscopic PbTe quantum wells, highlighting the role of edge channels and loops in maintaining coherence over large distances.

Findings

Conductance fluctuations observed in macroscopic PbTe wells.

Correlation field increases significantly from 40 mK to 1.2K.

Fluctuation amplitude remains near e^2/h despite large sample size.

Abstract

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.