Cavity-enhanced optical Hall effect in epitaxial graphene detected at terahertz frequencies
2016 (English)In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584Article in journal (Refereed) In press
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 1012 cmï¿œï¿œï¿œ2 range and a free hole mobility parameter as high as 1550 cm2/Vs. We also find that 6 ML EG shows n-type doping behavior with a much lower free electron mobility parameter of 470 cm2/Vs and an order of magnitude higher free electron density in the low 1013 cmï¿œï¿œï¿œ2 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.
Place, publisher, year, edition, pages
THz optical Hall effect, Epitaxial graphene, Free charge carrier properties
Physical Sciences Condensed Matter Physics Atom and Molecular Physics and Optics Ceramics
IdentifiersURN: urn:nbn:se:liu:diva-132407DOI: 10.1016/j.apsusc.2016.10.023OAI: oai:DiVA.org:liu-132407DiVA: diva2:1045443