Passive Q switching of an Er:phosphate glass laser using Er:Ca5(PO4)3F
(Er:FAP) as a saturable absorber intracavity (IC) load is described f
or the first time. Q-switched output was obtained consisting of a 6-mJ
single pulse of 83 ns full width at half maximum, with a 20% efficien
cy relative to the corresponding free-running output in the absence of
the IC Er:FAP load.