Highly nonlinear near-resonant photodarkening in a thulium-doped aluminosilicate glass fiber.
Permanent photoinduced optical attenuation has been observed in Tm(3+)-doped aluminosilicate glass fibers on exposure to near-resonance mode-locked 1064-nm radiation at 300 K. The rate of this darkening was observed to follow a 4.7 +/- 0.4 power dependence on the 1064-nm intensity. The result shows that absorption of infrared light of moderate intensity can lead to photoionization in rare-earth-doped glass, provided that a multiphoton stepwise excitation channel exists.
Broer
M M
MM
Krol
D M
DM
Digiovanni
D J
DJ