Realization of 5 h e 2 with graphene quantum Hall resistance array

Abstract

We report on the realization of 10 quantum Hall devices in series fabricated using epitaxial graphene on silicon carbide. Precision measurements with a resistance bridge indicate that the quantized Hall resistance across an array at a filling factor of 2 is equivalent to 5 h e 2 within the measurement uncertainty of approximately 4 × 10-8. A quantum Hall phase diagram for the array shows that a metrological quantization of 5 h e 2 can be achieved at the magnetic field of 6 T and a temperature of 4 K. This experiment demonstrates the possibility of timely unchangeable resistance reference in various ranges in relaxed experimental conditions.