Dynamic gain induced pulse shortening in Q-switched lasers

Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, Tampere 33101, Finland.
Optics Letters (Impact Factor: 3.18). 06/2008; 33(9):1011-3. DOI: 10.1364/OL.33.001011
Source: PubMed

ABSTRACT We describe a novel mechanism of pulse shortening in a Q-switched laser induced by the gain compression effect under strong pumping conditions. The pulse shortening requires a large variation of the gain excursion during the saturation process and benefits from the large volume of the gain medium. The effect has been experimentally demonstrated using a passive Q-switched Tm/Ho-doped fiber laser that shows gain-induced pulse compression from 800 ns down to 160 ns when the pump threshold is exceeded by 15 times.

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