1211.0446 (Lucas Barreto et al.)

Detecting the local transport properties and the dimensionality of
transport of epitaxial graphene by a multi-point probe approach    [PDF]

Lucas Barreto, Edward Perkins, Jens Johannsen, Søren Ulstrup, Felix Fromm, Christian Raidel, Thomas Seyller, Philip Hofmann

The electronic transport properties of epitaxial monolayer graphene (MLG) and hydrogen-intercalated quasi free-standing bilayer graphene (QFBLG) on SiC(0001) are investigated by micro multi-point probes. Using a probe with 12 contacts, we perform four-point probe measurements with the possibility to effectively vary the contact spacing over more than one order of magnitude, allowing us to establish that the transport is purely two-dimensional. Combined with the carrier density obtained by angle-resolved photoemission spectroscopy, we find the room temperature mobility of MLG to be (870+-120)cm2/Vs. The transport in QFBLG is also found to be two-dimensional with a mobility of (1600+-160) cm2/Vs.

View original: http://arxiv.org/abs/1211.0446