Electron Transport in Graphene Nanoribbon Field-Effect Transistor under Bias and Gate Voltages: Isochemical Potential Approach.
Zigzag graphene nanoribbon (zGNR) of narrow width has a moderate energy gap in its antiferromagnetic ground state. So far, first-principles electron transport calculations have been performed using nonequilibrium Green function (NEGF) method combined with density functional theory (DFT). However, the commonly practiced bottom-gate control has not been studied computationally due to the need to simulate an electron reservoir that fixes the chemical potential of electrons in the zGNR and electrodes. Here, we present the isochemical potential scheme to describe the top/back-gate effect using external potential. Then, we examine the change in electronic state under the modulation of chemical potential and the subsequent electron transport phenomena in zGNR transistor under substantial top-/back-gate and bias voltages. The gate potential can activate the device states resulting in a boosted current. This gate-controlled current-boosting could be utilized for designing novel zGNR field effect transistors (FETs).
Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Korea.|Department of Chemistry, Pohang University of Science and Technology , Pohang 37673, Korea.
Jeonghun
J
Yun
Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Korea.
Geunsik
G
Lee
Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Korea.
Kwang S
KS
Kim