Electrical and Optical Properties of Yb, Er doped GaAs

In this paper we report results from electrical and optical measurements carried out on GaAs:Yb, Er. For GaAs:Yb electrical experiments such as photoconductivity (PC) and Photo Induced Current Transient Spectroscopy (PICTS) show that there is a level at 0.65eV related to Yb. This explains why no Yb3+ photoluminescence (PL) emission is detected, the recombination energy of the trapped excitons is too low (~0.6eV) to excite the Yb3+ internal transition (~1.24eV). We also present results on Er doped GaAs materials. From PL experiments we deduce an estimate of 10–19 cm2 for the stimulated emission cross section. By PICTS and PC, we have evidenced a trap at 0.67eV related to Er ions in GaAs. And we think that in this case, the rare earth ions are excited via formation of bound excitons.