Understanding the 3D structure of GaAs nanowires

The effects of lamellar twinning in epitaxial particle-assisted GaAs <111>B nanowires are investigated in an extensive high resolution electron
microscopy (HRTEM) study of the low index zones <-100>, <-1-10>, <1-1-1> and
<1-1-2>. As these directions are non-parallel to the (-1-1-1) twin planes we find
that the twin segments exhibit two different zone axes as a consequence of
twinning. In the first three cases the alternative zones were found to be <1-2-2>
<11-4> and <11-5>. These findings are supported by a comparison of
experimental HRTEM images and multi-slice simulations along with fast
Fourier transform mapping. From the appearance of non-overlapping regions
we conclude that the nanowires are bound by {111} facets only. The twin
formation and the development of the stable side facets are discussed