Cavity-enhanced optical Hall effect in epitaxial graphene detected at terahertz frequencies

Nerijus Armakavicius, Chamseddine Bouhafs, Vallery Stanishev, Philipp Kühne, Rositsa Yakimova, Sean Knight, Tino Hofmann, Mathias Schubert, Vanya Darakchieva

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Cavity-enhanced optical Hall effect at terahertz (THz) frequencies is employed to determine the free charge carrier properties in epitaxial graphene (EG) with different number of layers grown by high-temperature sublimation on 4H-SiC(0001). We find that one monolayer (ML) EG possesses p-type conductivity with a free hole concentration in the low 10 12 cm −2 range and a free hole mobility parameter as high as 1550 cm 2 /Vs. We also find that 6 ML EG shows n-type doping behavior with a much lower free electron mobility parameter of 470 cm 2 /Vs and an order of magnitude higher free electron density in the low 10 13 cm −2 range. The observed differences are discussed. The cavity-enhanced THz optical Hall effect is demonstrated to be an excellent tool for contactless access to the type of free charge carriers and their properties in two-dimensional materials such as EG.

Original languageEnglish (US)
Pages (from-to)357-360
Number of pages4
JournalApplied Surface Science
Volume421
DOIs
StatePublished - Nov 1 2017

    Fingerprint

Keywords

  • Epitaxial graphene
  • Free charge carrier properties
  • THz optical Hall effect

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics
  • Physics and Astronomy(all)
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

Cite this

Armakavicius, N., Bouhafs, C., Stanishev, V., Kühne, P., Yakimova, R., Knight, S., Hofmann, T., Schubert, M., & Darakchieva, V. (2017). Cavity-enhanced optical Hall effect in epitaxial graphene detected at terahertz frequencies. Applied Surface Science, 421, 357-360. https://doi.org/10.1016/j.apsusc.2016.10.023