Tunable enhancement of exciton emission from MgZnO by hybridized quadrupole plasmons in Ag nanoparticle aggregation

Mg0.2Zn0.8O/metal nanoparticle systems have been fabricated and investigated. The photoluminescence results indicate that Al and Au nanoparticles could slightly enhance the near-band-edge (NBE) emission from Mg0.2Zn0.8O. In contrast, a giant and tunable NBE emission enhancement could be induced by Ag nanoparticles based on the coupling interaction between the hybridized quadrupole plasmon in Ag nanoparticle aggregation and the excitons of Mg0.2Zn0.8O. Interestingly, the intensity and position of the narrow quadrupole resonance could be controlled by tuning the interspace gap and size of Ag nanoparticles, which was clearly demonstrated both experimentally and theoretically. Our findings may pave the way for further development of high-efficiency UV light-emitting devices.