Near-mid infrared emission in Ce3 + and Tm3 + co-doped oxyfluoride glasses by excited at different wavelengths light

• The efficient energy transfer from Ce3 + to Tm3 + has been confirmed.
• Near-mid infrared emission was achieved excited by different wavelengths.
• This method may open a novel road to get near-mid infrared emission by sunlight directly.

A novel approach has been proposed to realize enhanced near-mid infrared emission in Ce3 + and Tm3 + co-doped oxyfluoride glasses excited at different wavelengths, whereby Ce3 + absorbs the photons in ultraviolet region and transfers the energy to Tm3 +, while Tm3 + converts the energy in visible and near infrared region into near-mid infrared region. For the purpose to achieve efficient near-mid infrared emission, ligand field theory has been adopted to optimize the glass host composition. The excitation, emission, time-resolved emission spectra and fluorescence decay curves have been measured to investigate the energy transfer (ET) from Ce3 + to Tm3 + and the generation mechanism of near-mid infrared emission. This approach will be of reference value for designing the gain medium of the near-mid infrared laser excited directly by the sunlight.