Enhanced photoluminescence of nonpolar p-type ZnO film by surface plasmon resonance and electron transfer

Nonpolar oriented Na-doped ZnO films were grown on m-plane sapphire substrates by plasma-assisted molecular beam epitaxy. The films show repeatable p-type conductivity with a hole concentration of about 3.0 x 10(16) cm(-3) as identified by the Hall-effect measurements. 10-fold enhancement in the near-band-edge ( NBE) emission of the nonpolar p-type ZnO by employing Pt nanoparticle surface plasmons has been observed. In addition, the deep level emission has been entirely suppressed. The underlying mechanism behind the enhancement of NBE emission and the quenching of defect emission is a combination of the electron transfer and the resonant coupling between NBE emission and Pt nanoparticle surface plasmons. (C) 2015 Optical Society of America