Source: http://aoot.osa.org/ome/abstract.cfm?uri=ome-7-12-4352
Timestamp: 2019-04-19 20:43:14+00:00

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Employing an acousto-optic modulator (AOM), the Q-switched laser characteristics of a Tm,Y:CaF2 crystal have been investigated. With T = 1%, 2% and 5% output couplers (OCs), output laser performance in both continuous-wave (CW) and Q-switching regimes have been presented and are discussed in details. The AOM Q-switched Tm,Y:CaF2 laser can run at high repetition rates ranging from 1 kHz to 10 kHz. Under the modulation frequency of 1 kHz, pulses with the shortest duration of 280 ns and the maximum pulse energy of 0.335 mJ have been delivered, corresponding to a maximum peak power of 1.19 kW. The results indicate that Tm,Y:CaF2 crystals can act as a promising candidate of gain medium for pulsed 2 μm laser.
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Fig. 1 Experimental setup of the actively Q-switched Tm,Y:CaF2 laser.
Fig. 3 The dependence of average output powers on absorbed pump powers under different PRFs.
Fig. 4 The dependences of (a) pulse durations, (b) pulse energies and (c) peak powers on PRFs at the maximum absorbed pump power in cases of T = 1%, 2% and 5% OCs.
Fig. 5 Temporal pulse profiles generated by acoustic-optically Q-switched Tm,Y:CaF2 laser.
Fig. 6 Output spectra in different operation regimes of Tm,Y:CaF2 laser.
Fig. 7 M2 factors of the acoustic-optically Q-switched Tm,Y:CaF2 laser under a PRF of 1 kHz at the maximum output power.

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