Optically pumped laser oscillation in the 1.6-1.8micron region from strained layer Al(0.4)Ga(0.6)Sb/GaSb/Al(0.4)Ga(0.6)Sb/double heterostructures grown by molecular beam hetero-epitaxy on Si substrates.

Double heterostructure lasers consisting of GaSb active layers with Al(0.4)Ga(0.6)Sb cladding layers were grown by molecular beam hetero-epitaxy on Si substrates. The intrinsic ~12 percent lattice mismatch between the GaSb and the Si at the growth temperature is largely taken up by a GaSb/AlSb superlattice. The GaSb layer is under severe dilatory strain at room temperature due to the larger thermal contraction of the GaSb layer relative to that of Si from the growth temperature and resulting in shrinkage of the GaSb bandgap. We have observed optically punped laser emission ranging from 1.63micron at 85K to 1.83micron at 350K. The exponential dependence of the threshold pump power and relative quantum efficiency exhibits a change in slope at ~250K. The exponential threshold-temperature dependence at 80 and 300K are T(o) = 158 and 100K, respectively, and are higher than previously reported for GaSB lasers. At 300K the threshold corresponds to an equivalent current density of 12 kA/cm(2).