Impact of thermal annealing on internal device parameters of GaAs_0.965Bi_0.035/GaAs_0.75P_0.25 quantum well lasers

摘要

The impact of post-growth thermal annealing on the internal device parameters such as internal loss (alpha(i)), internal differential quantum efficiency ($eta _0<^>{m d} $eta 0d) and modal material gain (Gamma g(0J)) of a single-quantum well (QW) laser diodes employing GaAs0.965Bi0.035/GaAs0.75P0.25 active regions and emitting near lambda similar to 980 nm was investigated. Parameter extraction from a conventional cavity length analysis indicates that the internal loss remains unchanged while internal differential quantum efficiencies degrade as the annealing time increases. Also, the variation of the modal material gain with annealing correlates to the corresponding change in the photoluminescence intensity. Comparisons between single- and double-QW devices indicate that the relatively high internal loss originates from the QW active region.