Résumé
We have grown semiconductor lasers by molecular beam epitaxy (MBE) on [100] oriented GaSb:Te substrates. An 80% internal quantum efficiency was deduced from measurements of the external quantum efficiency versus cavity length. Internal losses as low as 7 cm/sup -1/ have been found. The system is able to reach threshold current densities as low as 63 A/cm/sup 2/ per well for a cavity length of 1200 /spl mu/m. This is, to our knowledge, the best reported value at 2.26 /spl mu/m.