ROOM-TEMPERATURE PHOTON AVALANCHE UP-CONVERSION IN ER-DOPED ZBLAN GLASS

Photon avalanche up-conversion emission at 550 nm with a steep thresho ld has been observed in Er-doped ZBLAN glass. This is, to the best of our knowledge, the first time that this effect was found for Er3+ ion, in a glass, and at room temperature. The excitation wavelength is 579 .2 nm which is far away from any electronic absorption from the ground state. An extremely long rise time of the signal of up to about 4 s h as been observed for the up-converted emission at 550 nm. An excitatio n mechanism of this photon avalanche process is proposed.