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Laser-Induced Damage in Optical Materials
e quality of surface in the case of crystals is also linked to LID performance.
In the case of the titanium-doped sapphire used in the Ti:Sa ampliers, the surface
threshold in the nanosecond regime at 532nm is lower than that of the bulk mate-
rial (Sun etal. 1994, Bussiere etal. 2009). Sun evidences that the damage is induced
by a collection of micropits that he correlates to the presence of a nanometric surface
contaminant. Bussiere also stresses the diculty of polishing the Ti:Sa compared to
the nondoped sapphire, although in this case it is not supported by any measurement
(Bussiere eta