Quantized electron transport by interference-induced quantum dots of two cross-travelling surface acoustic waves

Xiang-Song Chen

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Quantized electron transport by interference-induced quantum dots of two cross-travelling surface acoustic waves

Xiang-Song Chen

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Abstract

In traditional approaches of obtaining quantized acoustoelectric current, a narrow channel is fabricated to form quantum dots, which hold a fixed number of electrons at a certain depth. We propose a natural way of forming quantum dots without the narrow channel, by the interference of two surface acoustic waves (SAWs) propagating across each other. A wide transportation area is defined by the usual (but widely separated) split-gate structure with another independent gate in between. This design can increase the quantized current by one to two orders of magnitude. The three-gate structure also allows separate control of the barrier height and the side-gate pinch-off voltage, thus avoids current leakage through the area beneath the side gates.

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Xiang-Song Chen. 2006-10-09. Quantized electron transport by interference-induced quantum dots of two cross-travelling surface acoustic waves. https://arxiv.org/abs/cond-mat/0610226

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