Annealing-induced changes of the 3.31 eV emission in ZnO nanorods

Effect of size and shape on the excitonic stimulated emission process in ZnO microstructures

“…37 The $3.31-eV band is likely to result from the stacking fault related transition 38,39 and/or the first LO phonon replica of the free exciton (FX-LO). 39,40 As the excitation fluence increases, one finds that two additional peaks grow on the lower energy side of the D 0 X band. One is the peak at 3.353 eV, which can be recognized in the PL spectra obtained at I ¼ 0.3 mJ/cm 2 or higher.…”