UV random laser in aluminum-doped ZnO nanorods

Vertically aligned Al-doped ZnO nanorods (AZO-NRs) were grown on glass substrate using a chemical bath deposition (CBD) method at various temperatures between 80°C and 130°C. The results showed the Al content in the AZO-NRs strongly depends on the growth temperature. The optimum doping level was attained at 110°C. The morphology was maintained in each sample, and the lasing properties were investigated against the Al-doped variation. The sample with a high doping level exhibited superior random lasing, with high intensity and spectral width of less than 0.08 nm. The same sample also had the lowest pumping threshold of 0.192 mW. More importantly, this study showed the possibility of utilizing doping as a tuning parameter for random lasing, whereby a 7.3 nm redshift in the lasing peak was observed with increasing doping concentration. This study also placed an emphasis on AZO-NRs as potential candidates for tunable random laser devices.