Fabrication and optimization of one-to-two and two-to-two optical directional couplers in glass using a femtosecond laser
Bibliographic record
Abstract
1x2 and 2x2 optical waveguide directional couplers were fabricated in a silica glass sample by a femtosecond laser and characterized at the wavelength of 1.5 μm. The coupling coefficient was determined by systematically writing series of 1x2 directional couplers. After the process and design optimization, the two types of waveguide directional couplers successfully achieved the coupling ratio of about 3.0 dB with the average IL and PDL 6.55 ± 0.25 dB and 0.28 ± 0.12 dB respectively. The multi-scan writing technique with inter-scan shifts was used to reshape the magnitude and profile of the refractive index change so that excess loss of S bends and the PDL for such couplers were substantially reduced.
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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 | 0.001 |
| 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".