It is widely accepted that the large Auger coefficient is the main cause for the large (~50%) efficiency droop in traditional hexagonal-phase indium gallium aluminium nitride (InGaAlN) LEDs. Yet this explanation is inadequate to account for the low efficiency droop in gallium arsenide (GaAs)- and gallium phosphide (GaP)-based LEDs, as those have similar Auger coefficients...
Source: http://www.semiconductor-today.com/news ... 0422.shtml