Graphene and derivatives of it (e.g. graphene-oxide, functionalised graphene) have
attracted a high scientific interest since it represents a stable monoatomically thin 2D carbon material and in particular due to graphene’s relativistic electronic band-structure. In consequence, the charge-carriers in graphene act as relativistic particles of zero effective mass showing associated phenomena like Klein-tunnelling or Veselago-lensing. On the other hand, graphene as well as all other mono-atomically flat 2D materials is basically only surface and therefore the electronic system is strongly susceptible to any type of environmental influence, e.g., type of substrate and substrate-induced scatterers, Fermi-level pinning, or scatterers imposed by adsorbates.
These two general properties enable a rich research-field from, both, the fundamental physics and application/novel devices view-point.
Main focus of research are the (spinpolarised) electronic transport in superstructured graphene addressing imposed potential superlattices (incl. magnetic) in the long-range limit and resulting scattering-phenomena, magnetolectric couplings, study of the impact of substrate surface-functionalisation and of direct graphene-functionalisation on Dirac-fermion correlations and scattering, as well as electrical properties of thin-film graphene-/zink-oxide and graphen-oxide/nanotube composites. Furthermore, the electronic transport in thin-films of size-selected MoS2 layers is investigated addressing layer-to-layer resistance and impact of different band-gaps. The different systems are experimentally studied by electrical transport measurements at room- and cryogenic temperatures and at static and transient magnetic fields.
Key-words: graphene, superstructure, superlattice, scattering, surface-functionalisation,
magnetotransport, graphene-oxide, MoS2, Hall-effect,
S. Hansel, M. Lafkioti, V. Krstić
“Suppression of short-range scattering via hydrophobic substrates and the fractional quantum Hall effect in graphene”
Phys. Status Solidi - Rapid Research Letter 6, 376 (2012)
Best of PSS 2013
M. Seredych, O. Mabayoje, M. Kolesnik, V. Krstić, T.J. Bandosz
“Zinc (hydr)oxide/graphene-oxide and graphene composites : Formation of new surface chemistry and enhancement in electrical conductivity”
J. Mater. Chem. 22, 7970 (2012)
V. Krstić, M. Glerup, S. Hansel, M. Lafkioti
”Doped single-walled carbon nanotubes and low-mobility graphene: impact of disorder and dopants on electronic magnetotransport”
Phys. Status Solidi - Rapid Research Letter 3, 187 (2009)
V. Krstić, D. Obergfell, S. Hansel, G.L.J.A. Rikken, J.H. Blokland, M.S. Ferreira, S. Roth
“Graphene-metal interface: two-terminal resistance of low-mobility graphene in high magnetic fields”
Nano Letters 8, p. 1700 (2008)
P. Stamenov, V. Krstić, J.M.D. Coey
“Shubnikov-de Haas and Hall quantum oscillations in graphite”
J. Mag. Mag. Mat. 290, p. 1402 (2005).