Linear and possible non-linear suppression of near-UV emission in ZnO inverted opal structures

Three-dimensional photonic crystals (PhCs) provide materials for the production of highly efficient light sources. In this respect, the channelling and suppression of the spontaneous emission (SE) due to the anisotropic nature of the photonic band gap (PBG), and band-edge stimulated emission, have been demonstrated. Various attempts have been reported on light emission in the telecommunication and visible wavelength ranges. For light emission in the ultraviolet region, ZnO stands out for its wide electronic band gap ~3.4eV and direct band-to-band transition.We report light emission in inverted opal ZnO structure, prepared by infiltration of ZnO onto the surface of Polystyrene opal matrix using low-temperature Atomic layer deposition technique, with subsequent inversion by firing the sample in air at 550degC for 30 minutes. The refractive index of 2.2 gives it a wide photonic band gap (PBG) that is preferable in the study of emission modulation of the embedded light source.