Why do output pulses split in actively Q-switched fiber lasers?
Bibliographic record
Abstract
Q-switched rare-earth-doped single-mode fiber lasers attract much attention in many applications. It is well know that in actively Q-switched solid-stage lasers, single output pulses observed in experiments are in good agreement with analytical solutions and numerical simulations. However, in actively Q-switched fiber lasers, the output pulses break into several sub-pulses in Q-switched envelopes. These phenomena have been reported in various actively Q-switched fiber lasers under different cavity schemes, pump and fiber conditions. Since dynamic distributions and evolutions of photon density and inversions in the laser cavities have not been effectively measured at the initial stage of Q-switching, the mechanism of these phenomena has remained uncertain in past two decades. Since the understanding of the related mechanism is critical to the design and development of laser systems, some conjectures have been proposed in the literature, based on experimental observations and analyses. Unfortunately, without careful examinations on the pulse initiation and evolution processes, the mechanism has not been exactly explained. In this paper, by investigating the initiation and formation of split pulses in typical actively Q-switched fiber lasers, the mechanism is exactly illustrated for the first time to the best of our knowledge. It is related to the evolution processes of the injected perturbation, and determined by the rise time of switching and conditions of photon density and inversions in Q-switching processes. Furthermore, based on this principle, some solutions to realize single-pulse output are proposed in this paper, and the simulated results are compared with the experimental ones.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".