Effects of localized trap-states and corrugation on charge transport in   graphene nanoribbons
  We investigate the role played by electron traps on adiabatic charge transport for graphene nanoribbons in the presence of an acoustically induced longitudinal surface acoustic wave (SAW) potential. Due to the weak longitudinal SAW-induced potential as well as the strong transverse confinement by a nanoribbon, minibandsof sliding tunnel-coupled quantum dots are formed so that by varying the chemical potential to pass through the minigaps, quantized adiabatic charge transport may be obtained. We analyze the way that the minigaps may be closed, thereby destroying the likelihood of current quantization in a nanoribbon. We present numerical calculations showing the effects due to electron traps which lead to localized-trap energy levels within the minigaps. Additionally, for comparison, we present results for the minibands of a corrugated nanoribbon in the absence of a SAW. 
Oleksiy Roslyak and Upali Aparajita and Godfrey Gumbs and Danhong   Huang
cond-mat.mes-hall