TY - JOUR T1 - Direct Simulation of Charge Transport in Graphene Nanoribbons AU - Nastasi , Giovanni AU - Camiola , V. Dario AU - Romano , Vittorio JO - Communications in Computational Physics VL - 2 SP - 449 EP - 494 PY - 2022 DA - 2022/01 SN - 31 DO - http://doi.org/10.4208/cicp.OA-2021-0032 UR - https://global-sci.org/intro/article_detail/cicp/20212.html KW - Graphene nanoribbons, bipolar charge transport, discontinuous Galerkin method. AB -
Graphene nanoribbons are considered as one of the most promising ways to
design electron devices where the active area is made of graphene. In fact, graphene
nanoribbons present a gap between the valence and the conduction bands as in standard semiconductors such as Si or GaAs, at variance with large area graphene which is
gapless, a feature that hampers a good performance of graphene field effect transistors.
To use graphene nanoribbons as a semiconductor, an accurate analysis of their
electron properties is needed. Here, electron transport in graphene nanoribbons is
investigated by solving the semiclassical Boltzmann equation with a discontinuous
Galerkin method. All the electron-phonon scattering mechanisms are included. The
adopted energy band structure is that devised in [1] while according to [2] the edge
effects are described as an additional scattering stemming from the Berry-Mondragon
model which is valid in presence of edge disorder. With this approach a spacial 1D
transport problem has been solved, even if it remains two dimensional in the wave-vector space. A degradation of charge velocities, and consequently of the mobilities, is
found by reducing the nanoribbon width due mainly to the edge scattering.