Oxychloride glass with low phonon energy as a choice for infrared laser materials

Recently, rare-earth-doped infrared (IR) luminescent glasses have drawn massive attention due to their potential applications in military, medical, and communications fields. In this Letter, we present a system of oxychloride Si-Ge-O-Cl glasses, suitable for rare-earth doping, which has been developed as a new, to the best of our knowledge, choice for IR luminescent materials. Raman spectra show a looser glass network because of the decreased phonon energy and density compared to the one in heavy-metal oxide glasses. The enhanced luminescence from the visible to the IR region has been obtained with a beneficial fluorescence decay time. The spectroscopy results indicate that the system of Si-Ge-O-Cl glasses may be a promising candidate for application in infrared laser materials with enhanced luminescence.