Al(0.37)Ga(0.63)As nanowires (NWs) were grown in a molecular beam epitaxy system on GaAs(111)B substrates. Micro-photoluminescence measurements and energy dispersive X-ray spectroscopy indicated a core-shell structure and Al composition gradient alon
g the NW axis, producing a potential minimum for carrier confinement. The core-shell structure formed during the growth as a consequence of the different Al and Ga adatom diffusion lengths.
