Implementation of a graphene quantum Hall Kelvin bridge-on-a-chip for resistance calibrations

Abstract

The unique properties of the quantum Hall effect allow one to revisit traditional measurement circuits with a new flavour. In this paper we present the first realization of a quantum Hall Kelvin bridge for the calibration of standard resistors directly against the quantum Hall resistance. The bridge design is particularly simple and requires a minimal number of instruments. The implementation here proposed is based on the bridge-on-a-chip, an integrated circuit composed of three graphene quantum Hall elements and superconducting wiring. The accuracy achieved in the calibration of a 12 906 Ω standard resistor is of a few parts in 10 8 , at present mainly limited by the prototype device and the interferences in the current implementation, with the potential to achieve few parts in 10 9 , which is the level of the systematic uncertainty of the quantum Hall Kelvin bridge itself.

Accurate graphene quantum Hall arrays for the new International System of Units

“…Arrays provide an elegant way to achieve quantized resistances at arbitrary levels via series and parallel connections of individual HBs 19 – 25 , while effectively increasing I C via parallel connections. These benefits have been recognized for decades, starting as early as 1993 with arrays for improved Wheatstone bridges 26 – 28 . The first reports on precision measurements for a modestly sized array was reported in 1999 29 .…”

Optimization of graphene-based quantum Hall arrays for recursive star–mesh transformations

“…Graphene, when grown epitaxially (EG), has been developed into devices for electrical metrology due to its robust quantum Hall effect (QHE) [1][2][3], and most EG-based devices that are used as resistance standards operate at the resistance plateau formed by the ν = 2 Landau level (𝑅 12906.4037 Ω). This common single-value constraint severely limits the infrastructure and equipment with which one may disseminate the unit of the ohm.…”