  Electronic structures for InxGa1-xAs nanowires with [100], [110], and [111]
orientations and critical dimensions of approximately 2 nm are treated within
the framework of density functional theory. Explicit band structures are
calculated and properties relevant to nanoelectronic design are extracted
including band gaps, effective masses, and density of states. The properties of
these III-V nanowires are compared to silicon nanowires of comparable
dimensions as a reference system. In nonpolar semiconductors, quantum
confinement and surface chemistry are known to play a key role in the
determination of nanowire electronic structure. InxGa1-xAs nanowires have in
addition effects due to alloy stoichiometry on the cation sublattice and due to
the polar nature of the cleaved nanowire surfaces. The impact of these
additional factors on the electronic structure for these polar semiconductor
nanowires is shown to be significant and necessary for accurate treatment of
electronic structure properties.
