Optically pumped laser oscillation in the 1.6-1.8 micron 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 heteroepitaxy on Si substrates. The intrinsic approximately 12-percent lattice mismatch between the GaSb and the Si at the growth temperature is largely taken up by a GaSb/AlSb superlattice. Optically pumped laser emission ranging from 1.63 microns at 85 K to 1.83 microns at 350 K has been observed. The exponential dependence of the threshold pump power and relative quantum efficiency exhibits a change in slope at about 250 K. The exponential threshold-temperature dependence at 80 and 300 K are T(0) = 158 and 100 K, respectively, and are higher than previously reported for GaSb lasers. At 300 K the threshold corresponds to an equivalent current density of 12 kA/sq cm.