Fig. 3: Numerical calculations of the effects of the series and transmission-line resistances on NDR performance.
From: Toward high-current-density and high-frequency graphene resonant tunneling transistors
a Output characteristics of RTT in which the drain current density Jd changes with the drain voltage Vd with different series-to-tunneling resistance ratios. The inset shows a cross-sectional schematic of the RTT with the resistances and current distribution marked, where rtun is the tunneling resistance per unit area, rc is the contact resistance per unit width between the metal and the graphene, rsg is the graphene sheet resistance outside the overlapping region, rtg is the top graphene sheet resistance in the overlapping region, rbg is the bottom graphene sheet resistance in the overlapping region. b PVR as a function of the series-to-tunneling resistance ratio. c, d Output characteristics with different transmission-line-to-tunneling resistance ratios. e PVR as a function of the transmission-line-to-tunneling resistance ratio. The arrows in (a, d) indicate forward and backward sweeps.
