Temperature Dependence of the Band-Edge Photoluminescence of Mn-Doped ZnO Ceramics

Abstract

We investigated of the near band-edge photoluminescence of the diluted magnetic semiconductor alloy Mn-doped ZnO. The near band-edge emissions of the excitonic transition were systematically investigated as a function of temperature. From the temperature dependence of the exciton peak, the Varshni temperature parameter, α, was found to increase with increasing Mn. From the temperature dependence of the FWHM of the emission line, the broadening factors, (T), were determined from fits to the data. The activation energies of thermal quenching were obtained for both the D 0X and the A 0X peaks from the temperature dependence of the bound exciton peaks. Finally, we show that at high temperatures, the broadening of the FWHM is dominated by the LO phonon interaction.