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It is well known that Neodymium glasses are widely used as active media in powerful picosecond laser systems. However, low thermal conductivity of glasses with broad bands of absorption and luminescence limits their use in pulsed lasers with high repetition rate. At the same time, disordered crystals having broad inhomogeneous bands of active ions and combining properties of both glasses and crystals may be reckoned as active media for ultrashort pulse lasers with high repetition rate. It has been shown recently that Calcium-Niobium-Gallium disordered garnet crystals doped with Nd3+ ions (CNGG:Nd3+) with broad inhomogeneous spectrum of amplification are prospective active media for the laser generation of powerful ultrashort pulses1 . In ref. 1 a passively mode-locked (PML) with a saturable dye absorber CNGG:Nd3+ laser generated trains of 7 ps pulses at a repetition rate of 0.3 Hz. To eliminate a liquid absorber and get an all solid state laser configuration one can mode-lock a laser actively with a crystalline modulator. But while the active mode-locking (AHL) technique may lead to the generation of high stable and reproducible laser pulses with a high repetition rate, its main drawback in comparison with the PML is relatively large pulse duration, in particular, at lamp pumping. Nevertheless, the use of a highly efficient LiNb03 acousto-optic modulator (AOMJ 2 •3 in a glass laser has led to the generation of pulses with duration of 13 ps 4 , so the operation of a laser on disordered crystals doped with Nd 3+ ions actively mode-locked with the AOM is a matter of considerable interest. It is known also that LiF crystals with F 2 color centers are successfully employed for passive Q-switching6 and the application of these crystals as passive Qswitchers to AHL lasers may give sufficient rise to pulse peak power. The aim of this work is to investigate the operation of actively mode-locked with LiNb03 AOM laser on a Calcium-Lithium-Niobium-Gallium disordered garnet crystal doped with Nd3+ ions (CLNGG:Nd3+) and a LiF:F2 passive Q-switch.
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