Optical studies of erbium excited states in Ga0.55Al0.45As

Photoluminescence experiments have been carried out on erbium doped Ga0.55Al0.45As under continuous wave and pulsed laser excitation. For the first time the emissions arising from the two first Er3+ excited states 4I11/2, 4I13/2 and their temperature dependence have been systematically studied. From these results the nature and the excitation‐deexcitation processes of these photoluminescences are discussed. With the help of these spectroscopic data we give an estimate of the stimulated emission cross section and the laser applications of such rare‐earth doped III‐V materials are examined.