Precision quantum Hall resistance (QHR) measurements were performed onlarge-area epitaxial graphene device at low magnetic fields (B = 2 T - 8 T) attemperature T = 1.5 K. Hall resistance was measured using Cryogenic CurrentComparator resistance bridge with high biasing current Isd = 40 micro ampere.The results showed that at B = 8 T the relative deviation of Hall resistancefrom the expected quantized value h/2e2 is within experimental uncertainty of3.5 parts in 108 and remained below 0.35 parts per million (ppm) down to B = 3T.
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