12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Precision comparison of the quantum Hall effect...
View graph of relations

« Back

Precision comparison of the quantum Hall effect in graphene and gallium arsenide

Research output: Contribution to journalJournal article

Published

  • T. J. B. M. Janssen
  • J. M. Williams
  • N. E. Fletcher
  • R. Goebel
  • A. Tzalenchuk
  • R. Yakimova
  • S. Lara-Avila
  • S. Kubatkin
  • Vladimir Falko
Journal publication date06/2012
JournalMetrologia
Journal number3
Volume49
Number of pages13
Pages294-306
Original languageEnglish

Abstract

The half-integer quantum Hall effect in epitaxial graphene is compared with high precision to the well-known integer effect in a GaAs/AlGaAs heterostructure. We find no difference between the quantized resistance values within the relative standard uncertainty of our measurement of 8.7 x 10(-11). The result places new tighter limits on any possible correction terms to the simple relation R-K = h/e(2), and also demonstrates that epitaxial graphene samples are suitable for application as electrical resistance standards of the highest metrological quality. We discuss the characterization of the graphene sample used in this experiment and present the details of the cryogenic current comparator bridge and associated uncertainty budget.