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arXiv · 0907.1010

Single Shot Charge Detection Using A Radio-Frequency Quantum Point Contact

M. C. Cassidy·A. S. Dzurak·R. G. Clark·K. D. Petersson·I. Farrer·D. A. Ritchie·C. G. Smith
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Abstract

We report on charge sensing measurements of a GaAs semiconductor quantum dot device using a radio frequency quantum point contact (rf-QPC). The rf-QPC is fully characterized at 4 K and milli-Kelvin temperatures and found to have a bandwidth exceeding 20 MHz. For single-shot charge sensing we achieve a charge sensitivity of 2x10^-4 e/(sqrt)Hz referred to the neighboring dot's charge. The rf-QPC compares favorably with rf-SET electrometers and promises to be an extremely useful tool for characterizing and measuring semiconductor quantum systems on fast timescales.

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M. C. Cassidy, A. S. Dzurak, R. G. Clark, K. D. Petersson, I. Farrer, D. A. Ritchie, C. G. Smith. 2009-07-06. Single Shot Charge Detection Using A Radio-Frequency Quantum Point Contact. https://doi.org/10.1063/1.2809370

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