Binary Josephson Array Power Standard

Project Description

Based on binary Josephson arrays we plan to develop a system for DC and AC power applications that allows a new representation of the Watt based on the Josephson effect.
Presently it is possible, using binary SINIS Josephson arrays, to synthesize sine waves with calculable rms values and 1 µV/V uncertainties at frequencies below 1 kHz. In a first step of the project this uncertainty of synthesized sine waves will be reduced by decreasing the transient times between quantized voltage steps.
In a mid-term period a two phase source for the frequency range up to 1 kHz will be developed and built. In a next step of the project optimized 10 V SINIS arrays will be implemented. Finally the system will be used for a new representation of the Watt with significantly reduced uncertainty.
It is expected that participants in the project have agreed to carry out significant research in this area at their institutes without receiving additional funding from this project. Formal development tasks and objectives in this project have been defined in the framework of EUROMET project 756.

Final Report 2007-12-12

Based on binary Josephson arrays we have developed a system for DC and AC power applications that allows linking representation of the Watt directly to the Josephson effect. First papers have been presented at the CPEM 2006, Turin, Italy, see e.g. [1, 2]. More presentations for the next CPEM 2008 in Boulder, USA, are in preparation.

A paper was presented at the metrology conference in Lille 2007, France, that summarizes most of the investigations of the project [3]. See also references therein.

[1] L. Palafox, G. Ramm, R. Behr, W:G: Kürten Ihlenfeld, and H. Moser., “Primary AC power standard based on programmable Josephson junction arrays”, IEEE Trans. Instr. Meas., vol. 56, no. 2, pp. 534-537, April 2007.
[2] C.J. Burroughs, S.P. Benz, P.D. Dresselhaus, Y. Chong, B. Waltrip, T. Nelson, J.M. Williams, D. Henderson, P. Patel, L. Palafox, and R. Behr, Development of a 60 Hz power standard using SNS programmable Josephson voltage standards IEEE Trans. Instr. Meas., vol. 56, no. 2, pp. 289-294, April 2007.
[3] R. Behr, L. Palafox, J.M. Williams, S. Djordjevic, G. Eklund, H.E. van den Brom, B. Jeanneret, J. Nissilä, A. Katkov, and S. P. Benz, “Binary Josephson Array Power Standard”, in proc Congrés International de Métrologie Lille 19-22 June 2007. ISBN: 2-915416-06-0

Electricity and Magnetism (EM)
Ralf Behr (PTB)
Coordinating Institute
PTB (Germany)