Quantum Hall resistance dartboards using graphene p-n junction devices with Corbino geometries

The use of multiple current terminals on millimeter-scale graphene p-n junction devices fabricated with Corbino geometries, or quantum Hall resistance dartboards, has enabled the measurement of several fractional multiples of the quantized Hall resistance at the ν = 2 plateau (RH ≈ 12 906 Ω). Experimentally obtained values agreed with the corresponding numerical simulations performed with the LTspice circuit simulator. More complicated designs of the quantum Hall resistance dartboard were simulated to establish the potential parameter space within which these Corbino-type devices could output resistance. Most importantly, these measurements support simpler processes of ultraviolet lithography as a more efficient means of scaling up graphene-based device sizes while maintaining sufficiently narrow junctions.