We demonstrate an intracavity self-synchronized multi-color Q-switched fiber laser using a parallel-integrated fiber Bragg grating(PI-FBG), fabricated by a femtosecond laser with a point-by-point parallel inscription ...We demonstrate an intracavity self-synchronized multi-color Q-switched fiber laser using a parallel-integrated fiber Bragg grating(PI-FBG), fabricated by a femtosecond laser with a point-by-point parallel inscription method. The multi-color Q-switched pulses can be always self-synchronized when the group delay differences between neighboring spectra range from-3.4 to 3.4 ps.The starting and evolution dynamics indicate that the saturable absorption effect of the carbon nanotube plays a dual role: synchronously triggering the startup of the pulse at successive colors by active Q-switching and spontaneously compensating to some extent the temporal walk-off of the multi-color pulses through the cross saturable absorption modulation. This work unveils the intracavity self-synchronization mechanism of the multi-color Q-switched pulses and also demonstrates the potential of PI-FBGs for the customizable generation of the synchronized multi-color pulse in a single cavity.展开更多
基金supported by the National Natural Science Foundation of China (No. 12274344)the Natural Science Basic Research Program of Shaanxi (No. 2023-JC-YB-563)the Guangdong Basic and Applied Basic Research Foundation (No. 2023A1515011517)。
文摘We demonstrate an intracavity self-synchronized multi-color Q-switched fiber laser using a parallel-integrated fiber Bragg grating(PI-FBG), fabricated by a femtosecond laser with a point-by-point parallel inscription method. The multi-color Q-switched pulses can be always self-synchronized when the group delay differences between neighboring spectra range from-3.4 to 3.4 ps.The starting and evolution dynamics indicate that the saturable absorption effect of the carbon nanotube plays a dual role: synchronously triggering the startup of the pulse at successive colors by active Q-switching and spontaneously compensating to some extent the temporal walk-off of the multi-color pulses through the cross saturable absorption modulation. This work unveils the intracavity self-synchronization mechanism of the multi-color Q-switched pulses and also demonstrates the potential of PI-FBGs for the customizable generation of the synchronized multi-color pulse in a single cavity.
