Atomic-scale simulation of semimetal-to-semiconductor transition in bismuth nanowires for future generation of nanoelectronic devices

In this paper we present first principle study on bismuth nanowires (BiNWs) with few nanometers in diameter which indicates that along trigonal crystallographic orientation a large bandgap in the order of few electron-volts is achievable due to quantum confinement. It is shown that there is a considerable dependency of the bandgap opening and surface reconstruction on the orientation. The results of density functional theory (DFT) are calibrated with Green's function screened Coulomb interaction (GW) corrections in this paper for the first time. We also report that for BiNWs with diameter less than 5 nm, the electron and hole effective masses are modified significantly in comparison with the values of bulk bismuth.