Blue Green Emission From a Cu $^{+}$ -Doped Transparent Material Prepared by Sintering Porous Glass

A colorless transparent, blue green emission material was fabricated by sintering porous glass impregnated with copper ions. The emission spectral profile obtained from Cu⁺ -doped high silica glass (HSG) by 267-nm monochromatic light excitation matches that obtained by pumping with an 800-nm femtosecond laser, indicating that the emissions in both cases come from an identical origin. The upconversion emission excited by 800-nm femtosecond laser is considered to be a three-photon excitation process. A tentative scheme of upconverted emission from Cu⁺ -doped HSG was also proposed. The glass materials presented herein are expected to find application in lamps, high density optical storage, and three-dimensional color displays.