Open AccessTransition of pulsed operation from Q-switching to continuous-wave mode-locking in a Yb:KLuW waveguide laser
Author(s) -
Jong Hoa Bae,
Xavier Mateos,
Magdalena Aguiló,
Francesc Dı́az,
Javier Rodríguez Vázquez de Aldana,
Carolina Romero,
Hansuek Lee,
Fabıan Rotermund
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.395701
Subject(s) - mode locking , optics , laser , saturable absorption , femtosecond , materials science , q switching , pulse (music) , waveguide , envelope (radar) , optoelectronics , physics , fiber laser , telecommunications , radar , detector , computer science
We report on the diverse pulsed operation regimes of a femtosecond-laser-written Yb:KLuW channel waveguide laser emitting near 1040 nm. By the precise position tuning of a carbon-nanotube-coated saturable absorber (SA) mirror, the transition of the pulsed operation from Q-switching, Q-switched mode-locking and finally sub-GHz continuous-wave mode-locking are obtained based on the interplay of dispersion and mode area control. The Q-switched pulses exhibit typical fast SA Q-switched pulse characteristics depending on absorbed pump powers. In the Q-switched mode-locking, amplitude modulations of the mode-locked pulses on the Q-switched envelope are observed. The radio-frequency spectrum represents the coexistence of Q-switching and mode-locking signals. In the purely mode-locked operation, the waveguide laser generates 2.05-ps pulses at 0.5 GHz.