title: Quantum confinement and electronic properties of silicon nanowires.
abstract: We investigate the structural, electronic, and optical properties of hydrogen-passivated silicon nanowires along [110] and [111] directions with diameter d up to 4.2 nm from first principles. The size and orientation dependence of the band gap is investigated and the local-density gap is corrected with the GW approximation. Quantum confinement becomes significant for d<2.2 nm, where the dielectric function exhibits strong anisotropy and new low-energy absorption peaks start to appear in the imaginary part of the dielectric function for polarization along the wire axis.
authors.affiliation: School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
authors.forename: Xinyuan
authors.initials: X
authors.lastname: Zhao
authors.forename: C M
authors.initials: CM
authors.lastname: Wei
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.forename: M Y
authors.initials: MY
authors.lastname: Chou