Weak Localization and Universal Conductance Fluctuations on Epitaxial Graphene Grown on the C-Face of 8°off-Axis 4H-SiC Substrates

Abstract

We report magnetotransport measurements in single epitaxial graphene layers grown on the C-face of an 8° off-axis 4H-SiC substrate using high temperature annealing conditions with a graphite cap covering the sample. The graphene sheets were found p-type doped, with mobilities varying between 1000 and 11000 cm²/V.s from device to device at 1.6 K. We examine the signature of weak localization and universal conductance fluctuations at weak magnetic field and we show that the phase coherence lengths extracted from the two phenomena are in satisfactory agreement.