We report on microscopic photoluminescence of a single V-shaped AlGaAs
/GaAs quantum wire. The experiments are performed at low temperature b
y selectively exciting 1 mu m(2) of the sample. The main photoluminesc
ence line is split into sharp peaks of width less than 0.5 meV and sep
arated by a few meV, The energy position and the Intensity of the peak
s are characteristic of the scanned quantum wire. First microphotolumi
nescence results suggest that localization phenomena are predominant i
n the quantum wire. They are due to the formation of extended monolaye
r-step islands, larger than the exciton radius, as in the case of high
-quality quantum wells. (C) 1997 American Institute of Physics. [S0003
-6951(97)00343-4].