Bi- and Yb-doped GaAs-AlGaAs low-threshold laser heterostructures with quantum well active layers

This work considers the experimental and calculated results concerning the LPE crystallization of GaAs, AlGaAs layers (10-30 nm) from Ga-Bi-melts at the temperature of 500-700°C. Bi being an isovalent impurity decreased the growth rate of GaAs layer to 0.01-0.1 nm/s and, at the same time, it deletes background impurities from a melt. When active layers of Al_xGa_1-XAs heterolaser (x=0.02-0.15) were doped by Yb and Bi it has been revealed that the conductivity inversion point is shifted towards lower concentration of Yb in a melt. Thus the low temperature LPE method and doping an active layer (Bi) allow the fabrication of low threshold injection semiconductor heterolaser