Static and dynamic responses of excitons in state-of-the-art bulk and epitaxial ZnO were analyzed to support the possible realization of polariton lasers. Free excitonic photoluminescence (PL) intensity at room temperature naturally increased with the increase in nonradiative lifetime (τ nr). The value of τnr was shown to increase with the decrease in gross density of positively and negatively charged and neutral point defects including complexes rather than with the decrease in Zn vacancies VZn density. The results indicate that the nonradiative recombination process is governed not by single point defects, but by certain defects introduced with the incorporation of VZn.
ASJC Scopus subject areas