Metrological applications of single-electron transport

Project Description

The proposed project aims to build on the successful collaboration between European NMIs in the field of single-electronics developed during the EU Framework IV ‘SETAMP’ and Framework V ‘COUNT’ projects. All methods for the controlled manipulation of single-electrons will be considered, including SETSAW and SQUID-based devices as well as traditional tunnel-barrier devices. There is a need for ongoing collaboration if quantum current standards based on counting single electrons are to be realized, and many NMIs have internally-funded projects in this area. Collaboration will focus on the following areas:

Fabrication and exchange of devices: A limited number of NMIs have facilities to fabricate nano-structures, so it is envisaged that some of this work will be carried out in collaboration with universities and other research institutes. The research community is continuing to produce new, promising, types of single-electron device (such as the ‘sluice’ developed at VTT in Finland), and there is a need for the metrological community to collaborate with such groups in a co-ordinated way.
Comparison of measurement systems: Information concerning the details of optimized measurement set-ups, such as cryogenic filters and rf sources will be exchanged to enable wider adoption of SET technology by the metrological community.
Small current calibration techniques: Since one of the main metrological applications of SET is in standards for small currents, it is proposed that the project also encompass exchange of information on traditional ‘non-quantum’ techniques for generating small currents or calibrating high-value resistors.
Primary capacitance standard: Charging a cryogenic capacitor with a known number of electrons could replace traditional capacitance realizations based on the calculable capacitor or quantum Hall effect. Several laboratories in Europe are contemplating experiments of this type, and the project will provide a forum for development of necessary techniques and components.
The metrological triangle: Pooling European NMI resources makes the closure of the electrical metrological triangle a possibility. This is considered as an important long-term goal of international metrology. One of the aims of the Euromet project will be to look at different scenarios for achieving it.

The project should run for a reasonable length of time so that significant research can be carried out, a period of 3-4 years is suggested.

Final Report 2010-04-15

The main achievement of the EURAMET project was to write a successful proposal for EMRP funding. SET research in now ongoing under the EMRP "REUNIAM" project.

Electricity and Magnetism (EM)
Stephen Giblin, NPL (United Kingdom)
Coordinating Institute
NPL (United Kingdom)