TUNABLE CR4+YSO Q-SWITCHED CR-LICAF LASER

Tunable passive Q-switching (781 nm to 806 nm at 300 K) of a flash-lam p pumped Cr3+:LiCaAlF6 (Cr:LiCAF) laser with a Cr4+:Y2SiO5 (Cr4+:YSO) broad-band solid-state saturable absorber has been realized, Typical p ulse widths of the Q-switched laser output ranged from 40 ns to 80 ns, depending on the lasing wavelength. Spectral narrowing and reduced be am diameter with the use of the saturable absorber were observed. The ground state and the excited state absorption cross sections of the Cr 4+:YSO absorber were found by bleaching experiments to be (7.0+/-1.4)x 10(-19) cm(2) and (2.3+/-0.5)x10(-19) cm(2) at 694 nm, respectively. N umerical simulation was utilized to simulate the Cr:LiCAF passive Q-sw itching with Cr4+:YSO solid-state saturable absorber.