We report on the observation of photoinduced absorption in four different thulium-doped ZBLAN fibers exposed to 1.12-μm light. The darkening rate is shown to follow a fourth-power dependence on the pumping intensity and a strong dependence on the Tm3+ concentration. The photoinduced absorption is observed mainly in the UV–visible part of the spectrum but extends slightly beyond 1 μm in the near-infrared.
© 1995 Optical Society of America
Original Manuscript: March 23, 1995
Published: December 15, 1995
P. Laperle, R. Vallée, and A. Chandonnet, "Photoinduced absorption in thulium-doped ZBLAN fibers," Opt. Lett. 20, 2484-2486 (1995)