We find that, under appropriate conditions, electrons can pass a barrier etched across a two dimensional electron gas (2DEG) by field emission from the GaAs/AlGaAs heterojunction into a second, low-density 2DEG formed deep in the substrate. The current-voltage characteristics exhibit a rapid increase in the current at the field emission threshold and intrinsic bistability above this threshold, consistent with a heating instability occurring in the second 2DEG. These results may explain similar behaviour recently seen in a number of front-gated devices by several groups.
@article{arxiv.cond-mat/9712275,
title = {Current flow past an etched barrier: field emission from a two-dimensional electron gas},
author = {D. H. Cobden and G. Pilling and R. Parthasarathy and P. L. McEuen and I. M. Castleton and E. H. Linfield and D. A. Ritchie and G. A. C. Jones},
journal= {arXiv preprint arXiv:cond-mat/9712275},
year = {2009}
}
Comments
9 pages, includes 4 eps figures, uses europhys.sty, to appear in Europhysics Letters