Temperature dependence of Auger recombination in gallium antimonide

Auger recombination in GaSb is of special interest because the energy gap E g and the valence band splitting Delta are nearly equal. This fact favours the valence band Auger process which involves the split-off band and gives it a particular temperature dependence. It is found that this Auger process increases strongly at low temperatures, reaches a maximum and decreases weakly at high temperatures. However, the maximum is not at T=125K where E g = Delta , but at T=95K where E g is somewhat larger than Delta . This behaviour is confirmed by experiments. Consequences for GaSb lasers are discussed.