1.54 μm photoluminescence of Er3+ doped into SiO2 films containing Si nanocrystals: Evidence for energy transfer from Si nanocrystals to Er3+

${\mathrm{SiO}}_2$ films containing Si nanocrystals (nc-Si) and Er were prepared and their photoluminescence (PL) properties were studied. The samples exhibited luminescence peaks at 0.81 and 1.54 μm, which could be assigned to the electron-hole recombination in nc-Si and the intra-4$f$ transition in ${\mathrm{Er}}^{\text{3+}},$ respectively. Correlation between the intensities of the two luminescence peaks was studied as functions of Er concentration and excitation power. The present results clearly demonstrate that excitation of ${\mathrm{Er}}^{\text{3+}}$ occurs through the recombination of photogenerated carriers spatially confined in nc-Si and the subsequent energy transfer to ${\mathrm{Er}}^{\text{3+}}$ .