Giblin, SP and Wright, SJ and Fletcher, JD and Kataoka, M and Pepper, M and Janssen, TJBM and Ritchie, DA and Nicoll, CA and Anderson, D and Jones, GAC (2010) An accurate high-speed single-electron quantum dot pump. NEW J PHYS , 12 , Article 073013. 10.1088/1367-2630/12/7/073013.
Using standard microfabrication techniques, it is now possible to construct devices that appear to reliably manipulate electrons one at a time. These devices have potential use as building blocks in quantum computing devices, or as a standard of electrical current derived only from a frequency and the fundamental charge. To date, the error rate in semiconductor 'tuneable-barrier' pump devices, those which show most promise for high-frequency operation, have not been tested in detail. We present high-accuracy measurements of the current from an etched GaAs quantum dot pump, operated at zero source-drain bias voltage with a single ac-modulated gate at 340 MHz driving the pump cycle. By comparison with a reference current derived from primary standards, we show that the electron transfer accuracy is better than 15 parts per million. High-resolution studies of the dependence of the pump current on the quantum dot tuning parameters also reveal possible deviations from a model used to describe the pumping cycle.
|Title:||An accurate high-speed single-electron quantum dot pump|
|Open access status:||An open access publication|
|UCL classification:||UCL > School of BEAMS > Faculty of Engineering Science > Electronic and Electrical Engineering|
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