Upconversion fluorescence spectroscopy of Er^(3+) doped lead oxyfluorosilicate g

Upconversion fluorescence emission of Er^(3+)-doped oxyfluorosilicate glass excited at 975 nm is experimentally investigated. The results reveal that the intense green and red emission, and weak blue emission centered at 525, 543, 655, and 410 nm, respectively. A two-photon upconversion process is a