Full text loading...
(a) Schematic of the simulated GaAs NW. (b) Top view of the atomic bond structure in the NW, where bonds are colored according to the bond length. (c) Top view of the color-coded slip-vector field.
(a) Schematic of the calculation of ad-atom energy map, where red circles and yellow lines represent Ga adsorption sites and Ga-As bonds in the top bilayer, respectively. The shell region is shaded in magenta. (b) and (c) Ga adatom energy along the blue and red lines marked in (a), respectively. (d) The adatom energy map of the entire NW top surface.
(a) Schematic of a GaAs bilayer island (magenta) nucleated at a corner of the top surface of a NW (cyan). (b) ZB (blue) and fault (red) island energies per atom as a function of the number of adatoms. The asymptotic limit of the ZB and fault energies are indicated by the blue and red arrows, respectively.
(a) Gibbs free-energy changes of ZB (blue) and fault (red) islands of a Ga-As bilayer adsorbed on the GaAs NW as a function of the island diameter at temperature T = 1030 K (solid lines) and 1050 K (dashed lines). The peak position (i.e., the critical nucleus size) of each curve is indicated by an arrow. (b) Critical nucleus sizes of ZB (blue) and fault (red) islands as a function of the temperature. The yellow area indicates (D W, T) pairs, for which NWs are grown free of SF. The vapor pressures are P Ga = 2.7 × 10−6 bar and P As = 5 × 10−4 bar.
Article metrics loading...