Co2+:LiGa5O8 saturable absorber passive Q switch for 1.34 μm Nd3+:YAlO3 and 1.54 μm Er3+:glass lasers

Passive Q switching of a Nd3+:YAlO3 laser at 1.34 mu m and an Er3+: glass laser at 1.54 mu m was demonstrated using a Co2+:LiGa5O8 crystal as a saturable absorber. Q-switched pulses at 1.34 mu m of 13 mJ energy and 90 ns duration and at 1.54 mu m of 8 mJ energy and 70 ns duration were obtained. The ground state absorption cross section of the Co2+:LiGa5O8 was estimated to be (2.6 +/- 0.4)x10(-19) cm(2) and (2.5 +/- 0.5)x10(-19) cm(2) at 1.34 and 1.54 mu m, respectively. The T-4(1)(F-4)-->(4)A(2) relaxation time of the Co2+ ion in the LiGa5O8 crystal was measured to be similar to 130 ns. (C) 2000 American Institute of Physics. [S0003-6951(00)04342-4].