Thickness Dependence on Wavelength Range of Random Laser in Ultrathin ZnO Crystals Grown by Mist-CVD on C-plane Sapphire Substrate

Abstract

The ultrathin ZnO crystals were grown by mist chemical vapor deposition technique with potentially low-cost and low-environmental impact on commercially available c-plane sapphire substrates. The photoluminescence spectra of the ultrathin ZnO crystals were evaluated, and we observed the random lasing behaviors. In addition, the range of random laser wavelengths of photoluminescence can be shifted with a constant trend by changing the structural parameters of the ultrathin ZnO crystals. Here, the structural parameter was the thickness of the ultrathin ZnO crystals. The results indicate that the oscillation wavelength range of the random laser may be potentially fine-tuned by changing the structural parameters of the random laser medium.