Term: mode-locked laser
https://doi.org/10.1351/goldbook.M03959

Definition:
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).

Related Terms:
1) free-running laser (http://doi.org/10.1351/goldbook.F02521).
2) laser (http://doi.org/10.1351/goldbook.L03459).
3) coupling (http://doi.org/10.1351/goldbook.C01025).
4) absorber (http://doi.org/10.1351/goldbook.A00034).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2254 (https://doi.org/10.1351/pac199668122223)

Citation: 'mode-locked laser' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03959

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