A Semiconductor core-shell nanowire is grown by first growing a nanowhisker, then epitaxially depositing a shell material. These structures usually have a hexagonal cross section. Combinations of core and shell materials with different bulk lattice constants result in strain which alters the electronic band structure. The figure below shows a nanowire and the bandedge energies along a line perpendicular to the axis of the wire. Since the strain depends on the relative sizes of the core and shell, but not on their absolute sizes, there will be different band structure for each core/shell ratio.
The band diagrams along lines and 2D slices are available here.
Displaying a spatially dependent band structure for each core/shell ratio is not practical, so we simplify each band structure by considering the extrema of the valence band, conduction band Gamma-point and X-point, and taking their mean values each within the core and shell materials. These six energies can then be plotted as a function of the relative size of the core radius, as shown below:
Core-shell wire band diagrams for different core materials:
AlAs AlP AlSb
GaAs GaP GaSb
InAs InP InSb
Nitrides
Core-shell wire band energies in a single text file: core-shell-energies
Core-shell effective masses for different core materials:
AlAs AlP AlSb
GaAs GaP GaSb
InAs InP InSb
Nitrides
Core-shell effective masses in a single text file: core-shell-masses