Figure 3: Results of the time-resolved transport measurement for the graphene device with a top gate.
From: Plasmon transport in graphene investigated by time-resolved electrical measurements
(a) Current as a function of time at B=12 T for several values of Vtg. Traces are vertically offset for clarity. The charge neutrality point is located at Vtg=−85 V and the electron density increases with Vtg. (b,c) Velocity of the charge pulse in the gated region for B=12 and 8 T. The path length is 0.2 mm. Black traces represent Rxx. (d) Velocity at peaks in QH states plotted as a function of the carrier density. In addition to the data points taken from b and c, those for ν=2 at B=4 and 2 T are included. The solid curve represents v
n1/4. (e) Log–log plot of the velocity at peaks normalized by 
as a function of w/d, where 
. Solid black line is 
. Blue and red curves are the normalized velocity calculated by using equations 2 and 3, respectively. Grey and green lines with an error bar represents the normalized velocity at ν=2 and 6 in the ungated sample, respectively.
