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Current flow past an etched barrier: field emission from a two-dimensional electron gas

D. H. Cobden·G. Pilling·R. Parthasarathy·P. L. McEuen·I. M. Castleton·E. H. Linfield·D. A. Ritchie·G. A. C. Jones
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Abstract

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.

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D. H. Cobden, G. Pilling, R. Parthasarathy, P. L. McEuen, I. M. Castleton, E. H. Linfield, D. A. Ritchie, G. A. C. Jones. 1997-12-23. Current flow past an etched barrier: field emission from a two-dimensional electron gas. https://doi.org/10.1209/epl%2Fi1998-00151-4

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