Fig. 3

Proposed growth mechanism of In_xGa_1−xSb nanowires. a Transmission electron microscopy image of the tip region of a typical In_0.28Ga_0.72Sb nanowire (NW). The gray scale denotes the measured intensity. b Energy-dispersive X-ray spectroscopy line scan across the NW tip, neck and body in the axial direction. The location of the line scan is indicated by the blue colored line in panel (a). c Illustrative schematics of four different proposed growth steps involved during the NW growth. They are: (i) formation of the gold (Au) nanoparticle, (ii) formation of the AuIn alloy, (iii) In precipitation from the AuIn alloy, (iv) formation of In_xGa_1−xSb neck with the increasing Ga concentration, and (v) growth of In_xGa_1−xSb NW with the steady Ga concentration