We report a firm evidence of enhanced luminescence from InGaN-like clusters in InxAlyGa1-x-yN quaternary alloys. Photoluminescence (PL) and Raman scattering measurements have been employed to study the optical properties of these alloys. The excellent correlation between the phonon replica structures accompanying luminescence line and the observed InGaN-related phonon modes in Raman spectra provide a powerful evidence showing that the existence of InGaN-like clusters is responsible for the enhanced luminescence in InxAlyGa1-x-yN quaternary alloys. In addition, the dependence of the PL emission energy on temperature in the low-temperature regime and on excitation power density can also be explained consistently with recombination mechanisms involving the localized states attributed to InGaN-like cluster size fluctuations.
|Number of pages||3|
|Journal||Applied Physics Letters|
|State||Published - Feb 25 2002|