R K /100 and RK/200 quantum Hall array resistance standards

Abstract

It is theoretically possible to combine several Hall bars in arrays to define quantum standards with perfectly quantized resistance values. We have thus developed and fabricated 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 109 for supplying currents up to 2 mA at a temperature of 1.3 K. 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 dissipationless. This work, therefore, demonstrates the efficiency of the multiple connections technique and consequently that QHARS are likely to extend the quantum Hall effect metrological applications.