Double-handed circular Bragg reflection bands in chiral thin films
Bibliographic record
Abstract
Titanium dioxide was evaporated onto rotating substrates at highly oblique deposition angles to create thin films exhibiting a nanostructure which resembles a polygonal helix. Abrupt, periodic rotations of the substrate were used to create triangle, square, pentagon, and star-shaped film morphologies. Experimental optical measurements show that polygonal-helix thin-films exhibit double-handed circular Bragg phenomena. Unlike a standard chiral filter, a polygonal-helix thin-film reflects left-handed circularly polarized light at one frequency band and right-handed circularly polarized light at a second frequency band. The relative wavelength-dependence of the reflection bands is controlled by the angular rotation between arms of a polygonal helix. Spectral-hole polarization filters, produced by adding twist and layer defects to a polygonal helix, are also reported. Twist-defects tend to produce a narrow passband within both circular Bragg reflection bands of a polygonal helix, while a spacing layer defect can be used to produce a passband within only one of the reflection bands.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".