Polymer-encapsulated molecular doped epigraphene for quantum resistance metrologyShow others and affiliations
2019 (English)In: Metrologia, ISSN 0026-1394, E-ISSN 1681-7575, Vol. 56, no 4, article id 045004Article in journal (Refereed) Published
Abstract [en]
One of the aspirations of quantum metrology is to deliver primary standards directly to end-users thereby significantly shortening the traceability chains and enabling more accurate products. Epitaxial graphene grown on silicon carbide (epigraphene) is known to be a viable candidate for a primary realisation of a quantum Hall resistance standard, surpassing conventional semiconductor two-dimensional electron gases, such as those based on GaAs, in terms of performance at higher temperatures and lower magnetic fields. The bottleneck in the realisation of a turn-key quantum resistance standard requiring minimum user intervention has so far been the need to fine-tune the carrier density in this material to fit the constraints imposed by a simple cryo-magnetic system. Previously demonstrated methods, such as via photo-chemistry or corona discharge, require application prior to every cool-down as well as specialist knowledge and equipment. To this end we perform metrological evaluation of epigraphene with carrier density tuned by a recently reported permanent molecular doping technique. Measurements at two National Metrology Institutes confirm accurate resistance quantisation below 5n-1. Furthermore, samples show no significant drift in carrier concentration and performance on multiple thermal cycles over three years. This development paves the way for dissemination of primary resistance standards based on epigraphene
Place, publisher, year, edition, pages
Institute of Physics Publishing , 2019. Vol. 56, no 4, article id 045004
Keywords [en]
grapheme, measurement standards, molecular doping, quantum Hall effect, Carrier concentration, Electric corona, Gallium arsenide, Graphene, III-V semiconductors, Semiconducting gallium arsenide, Semiconductor doping, Silicon carbide, Two dimensional electron gas, Epitaxial graphene, National metrology institutes, Quantum Hall resistance, Quantum resistance, Resistance standards
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-39831DOI: 10.1088/1681-7575/ab2807Scopus ID: 2-s2.0-85070555097OAI: oai:DiVA.org:ri-39831DiVA, id: diva2:1356535
2019-10-012019-10-012024-05-21Bibliographically approved