Quantum Hall resistance standards from graphene grown by chemical vapor deposition on silicon carbide

TL;DR

This paper demonstrates that graphene grown by chemical vapor deposition on SiC can serve as a reliable quantum Hall resistance standard, achieving high accuracy over a broad magnetic field range at relatively low magnetic fields and temperature.

Contribution

It reports the first high-accuracy quantum Hall resistance standard using CVD-grown graphene on SiC, operable from 10 T to 19 T at 1.4 K, with a scalable growth and fabrication process.

Findings

Achieved quantum Hall resistance accuracy within 10^{-9} from 10 T to 19 T.

Demonstrated low-dissipation quantum Hall effect in CVD graphene on SiC.

Showed potential for replacing GaAs-based standards with scalable graphene technology.

Abstract

Replacing GaAs by graphene to realize more practical quantum Hall resistance standards (QHRS), accurate to within $10^{-9}$ in relative value, but operating at lower magnetic fields than 10 T, is an ongoing goal in metrology. To date, the required accuracy has been reported, only few times, in graphene grown on SiC by sublimation of Si, under higher magnetic fields. Here, we report on a device made of graphene grown by chemical vapour deposition on SiC which demonstrates such accuracies of the Hall resistance from 10 T up to 19 T at 1.4 K. This is explained by a quantum Hall effect with low dissipation, resulting from strongly localized bulk states at the magnetic length scale, over a wide magnetic field range. Our results show that graphene-based QHRS can replace their GaAs counterparts by operating in as-convenient cryomagnetic conditions, but over an extended magnetic field range. They rely on a promising hybrid and scalable growth method and a fabrication process achieving low-electron density devices.