Effect of the intra-layer potential distributions and spatial currents on the performance of graphene SymFETs

Abstract

In this paper, a two-dimensional (2-D) model for a graphene symmetric field effect transistor (SymFET), which considers (a) the intra-graphene layer potential distributions and (b) the internal current flows through the device, is presented and discussed. The local voltages along the graphene electrodes as well as the current-voltage characteristics of the device are numerically calculated based on a single-particle tunneling model. Our numerical results show that: (i) when the tunneling current is small, due to either a large tunneling thickness (≥ 2 atomic layers of BN) or a small coherence length, the voltage distributions along the graphene electrodes have almost zero variations upon including these distributed effects, (ii) when the tunnel current is large, due to either a small tunneling thickness (∼ 1 atomic layer of BN) or due to a large coherence length, the local voltage distributions along the graphene electrodes become appreciable and the device behavior deviates from that predicted by a 1-D approximation. These effects, which are not captured in one-dimensional SymFET models, can provide a better understanding about the electron dynamics in the device and might indicate potential novel applications for this proposed device.

High‐modulation depth modulator based on double‐layer graphene with a low bias voltage

“…Graphene is a two‐dimensional (2D)‐honeycomb‐lattice material which has drawn an increase in research because of its excellent properties, such as high‐electron mobility, tunable chemical energy and Hall effect at room temperature since it was peeled off from carbon in 2004 [6–9]. There is a great prospect that graphene can improve the performance of communication devices, especially in modulators [10].…”