Two-Colour Nonlinear Amplification for Mid-infrared Generation by Difference Frequency Generation
Bibliographic record
Abstract
In this thesis, I discuss the development of a two-colour laser system which uses an all-normal dispersion fiber laser in combination with a gain-managed nonlinear amplifier as its broadband source. The goal is to develop a two-colour laser which can be used for mid-infrared generation through difference frequency generation. Most molecules contain characteristic absorption features in the mid-infrared ”molecular fingerprint” region from 3 - 20 μm. Our goal is to create a high power laser that can access as much of these wavelengths as possible. This requires a wide wavelength separation between colours, along with broad bandwidths in each colour, while attaining high pulse energies. This work shows the use of nonlinear amplification of a two-colour seed in an Yb:fiber in order to combat gain narrowing and maintain broad wavelengths in the two colours through self-phase modulation. Many different experimental setups were implemented, which will be presented, with the most successful results being achieved with the use of a large-mode- area Yb:fiber. We demonstrate a two-colour laser source with colours centered at 1070 nm and 1120 nm with individual bandwidths of 30 nm and 21 nm respectively. This two-colour spectrum was amplified up to a total power of 6.76 W, with a repetition rate of 9.67 MHz, corresponding to a total pulse energy of 700 nJ.
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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 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 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".