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arXiv · cond-mat/0203231

RK/100 and RK/200 Quantum Hall Array Resistance Standards

Abstract

It is theoretically possible to combine several Hall bars in arrays to define new quantum standards with perfectly quantized resistance values. We have thus, for the first time, developed and fabricated novel Quantum Hall Array Resistance Standards (QHARS) made of a large number N (N=100, 50) of Hall bars placed in parallel using a triple connections technique. The Hall resistance of these quantum standards is found to be very well quantized. On the i=2 Hall plateau, the resistance of specific good arrays stays equal to RK/2N within 5 parts in 10^9 for supplying currents up to 2 mA at a 1.3 K temperature. The mean longitudinal resistance of the Hall bars which constitute the arrays has been determined through the analysis of the array equivalent electrical circuit. This measurement shows that the carrier transport in the Hall bars is dissipation-less. This work therefore demonstrates the efficiency of the multiple connections technique and consequently that QHARS are likely to extend the QHE metrological applications.

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W. Poirier, A. Bounouh, K. Hayashi, H. Fhima, F. Piquemal, G. Geneves, J. P. Andre. 2002-06-27. RK/100 and RK/200 Quantum Hall Array Resistance Standards. https://doi.org/10.1063/1.1495893

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