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Ballistic electron transport exceeding 160 microns in an undoped GaAs/AlGaAs FET

G. R. Facer·B. E. Kane·A. S. Dzurak·R. J. Heron·N. E. Lumpkin·R. G. Clark·L. N. Pfeiffer·K. W. West
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Abstract

We report measurements of GaAs/AlGaAs undoped field-effect transistors in which two-dimensional electron gases (2DEGs) of exceptional quality and versatility are induced without modulation doping. Electron mobilities at T=4.2 K and density 3 E11 /cm^2 exceed 4 E6 cm^2/Vs. At lower temperatures, there is an unusually large drop in scattering, such that the mobility becomes too high to measure in 100 micron samples. Below T=2.5 K, clear signatures of ballistic travel over path lengths in excess of 160 microns are observed in magnetic focusing experiments. Multiple reflections at the edges of the 2DEG indicate a high degree of specularity.

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G. R. Facer, B. E. Kane, A. S. Dzurak, R. J. Heron, N. E. Lumpkin, R. G. Clark, L. N. Pfeiffer, K. W. West. 1998-06-26. Ballistic electron transport exceeding 160 microns in an undoped GaAs/AlGaAs FET. https://arxiv.org/abs/cond-mat/9805197

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