Comparison of Er~(3+) Photoluminescence and Photoluminescence Excitation Spectroscopy in In-situ-doped GaN:Er and Er-implanted GaN

摘要

Site-selective photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies have been carried out at 6 K on the ~1540 nm ~4I_(13/2) →~4I_(15/2) Er~(3+) transition in in-stiu-doped GaN:Er grown by molecular beam epitaxy. The results are compared with site-selective PL and PLE studies of ion-implanted GaN:Er which have detected nine different Er~(3+) sites and associated PL spectra. Three distinct Er~(3+) sites are identified in the in-situ-doped samples. For the in-situ-doped samples, the concentrations of the various Er~(3+) sites are comparable while for the ion-implanted sample, the concentration of one Er~(3+) site was higher than the concentration of the other sites. In-situ-doped samples grown with different Er-cell temperatures were considered, and the width of the PLE spectrum appears to be a function of the Er-cell temperature.