Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 29: Graphene: Structural Properties (organized by O)
TT 29.1: Talk
Monday, March 31, 2014, 16:00–16:15, WIL C107
Vertical height of quasi-free standing monolayer graphene on SiC(0001): an XSW study — •J. Sforzini1, T. Denig2, T. L. Lee3, C. Kumpf1, S. Subach1, U. Starke2, F. C. Bocquet1, and F.S. Tautz1 — 1Peter Grünberg institute (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany — 2Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany — 3Diamond light source ltd, Harwell oxford, Didcot, Oxfordshire, United Kingdom
We investigated a quasi-free standing monolayer graphene sample[1] on SiC(0001) obtained by decoupling the buffer-layer from Si-terminated surface by hydrogen intercalation. We used X-ray Standing Wave technique (XSW), combining dynamical diffraction and X-ray photoelectron spectroscopy, to detect the coherent distribution of the chemically different species (Si and C) at the interface. Our analysis shows two different carbon species (C in the graphene layer and C in the SiC bulk); we find that the adsorption height of the graphene layer is slightly higher than theoretically predicted. The discrepancy, attributed to the very weak graphene-substrate intercation, is still challenging for theory[2].
[1]Riedl, et. al., PRL, 103, 246804 (2009)
[2]Deretzis , et. al., Nanoscale, 5, 671-680 (2012)