Characterization of up-conversion processes in Tm3+-doped LiNbO3

Up-conversion processes in Tm3+-doped LiNbO3 under single wavelength excitation through 3H6→3H4 absorption band (around 800 nm) have been studied. Emissions arising from the 1D2 and 1G4 upper excited states are generated. The different excitation mechanisms and the dependence on Tm3+ concentration have been investigated.