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An improved 2.5 GHz electron pump: single-electron transport through shallow-etched point contacts driven by surface acoustic waves

P. Utko·K. Gloos·J. B. Hansen·P. E. Lindelof
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Abstract

We present an experimental study of a 2.5 GHz electron pump based on the quantized acoustoelectric current driven by surface acoustic waves (SAWs) through a shallow-etched point contact in a GaAs/AlGaAs heterostructure. At low temperatures and with an additional counter-propagating SAW beam, up to n = 20 current plateaus at I=nef could be resolved, where n is an integer, e the electron charge, and f the SAW frequency. In the best case the accuracy of the first plateau at 0.40 nA was estimated to be dI/I = +/- 25 ppm over 0.25 mV in gate voltage, which is better than previous results.

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P. Utko, K. Gloos, J. B. Hansen, P. E. Lindelof. 2003-11-04. An improved 2.5 GHz electron pump: single-electron transport through shallow-etched point contacts driven by surface acoustic waves. https://arxiv.org/abs/cond-mat/0311060

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