We present detailed experimental studies of the temperature dependence of the plateau conductance of GaAs quantum point contacts in the temperature range from 0.3 K to 10 K. Due to a strong lateral confinement produced by a shallow-etching technique we are able to observe the following unexpected feature: a linear temperature dependence of the measured mid-plateau conductance. We discuss an interpretation in terms of a temperature dependent, intrinsic series resistance, due to non-ballistic effects in the 2D-1D transition region. These results have been reproduced in several samples from different GaAs/GaAlAs heterostructures and observed in different experimental set-ups.
@article{arxiv.cond-mat/0208452,
title = {Temperature dependent deviations from ideal quantization of plateau conductances in GaAs quantum point contacts},
author = {A. E. Hansen and A. Kristensen and H. Bruus},
journal= {arXiv preprint arXiv:cond-mat/0208452},
year = {2007}
}
Comments
7 pages, 6 figures; to appear in proceedings of ICPS 2002, Edinburgh