A
laser in which many resonant modes are coupled in phase, to yield a train of very short
pulses (e.g. ps pulses). The
coupling of the modes is obtained by modulation of the gain in the resonator, and can be active
(electro-optic modulation of the losses or of the pump intensity), or passive (with
a saturable
absorber).
Source:
PAC, 1996, 68, 2223
(Glossary of terms used in photochemistry (IUPAC Recommendations 1996))
on page 2254