Abstract
The growth by molecular‐beam epitaxy of high‐quality Ga0.85In0.15As0.13Sb0.87 active layers with Al0.4Ga0.6As0.035Sb0.965 cladding layers on GaSb substrates by molecular‐beam epitaxy is reported. The lattice match of the active layer to the substrate is Δa/a ∼4 ×103. Optically pumped laser oscillation was observed from 80 to 300 K with T0=55 K for TT0=32 K for 225<T<300 K.