The origin of this phenomenon and its consequences on the electronic band structure are discussed. The core morphology affects the shell structure involving plane bending and the formation of low-angle polar boundaries. To unveil those mechanisms, we perform atomic-scale aberration-corrected scanning transmission electron microscopy studies on planar core-shell nanowires on α-Al 2O 3 substrates. Strain relaxation mechanisms during epitaxial growth of core-shell nanostructures play a key role in determining their morphologies, crystal structure and properties.
