Carrier Transport Properties of Bilayer Graphene Obtained via Hall Measurements

The electron transport characteristics of bilayer graphene were investigated in terms of changes in the temperature from 2 to 300 K. The purpose of this study was a confirming the reported values5 of the carrier density and the mobility for using a ballistic quantum transport experiment. The mechanical exfoliation method was adopted to get the best quality of bilayer graphene and the number of layers of graphene was identified by the Raman spectra. Our bilayer graphene was a slightly n-doped state with the neutrality point at Vg = -7.5 V. Hall measurements provided an accurate means to evaluate the carrier density and the mobility. In magnetic field of -9 to 9 T, clear Shubnikov-de Haas oscillations were measured in bilayer graphene, indicating the presence of a clear electron quantum transport mechanism. The mobility and the carrier density of the bilayer graphene at 2 K were measured to be 9,400 cm2/V·s and 3 x 10(11) cm(-2), respectively.