Room-temperature random telegraph noise in luminescence from macroscopic InGaN clusters

We report on photoluminescence properties of individual macroscopically sized InGaN clusters that were formed in InGaN multiple quantum wells. Phase separation in InGaN results in the formation of clusters with a size of 1-2 mum with three different indium compositions. A small fraction (one in 100-1000) of the clusters shows random telegraph noise in luminescence at room temperature. Superlinear dependence of the luminescence switching rate on excitation intensity indicates that the switching is induced by the cooperation of multiple carriers. (C) 2001 American Institute of Physics.