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Bibliographic record
Abstract
The pyrochlore magnet ${\mathrm{Yb}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ has been proposed as a quantum spin ice candidate, a spin liquid state expected to display emergent quantum electrodynamics with gauge photons among its elementary excitations. However, ${\mathrm{Yb}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$'s ground state is known to be very sensitive to its precise stoichiometry. Powder samples, produced by solid-state synthesis at relatively low temperatures, tend to be stoichiometric, while single crystals grown from the melt tend to display weak ``stuffing'' wherein $\ensuremath{\sim}2%$ of the ${\mathrm{Yb}}^{3+}$, normally at the $A$ site of the ${A}_{2}{B}_{2}{\text{O}}_{7}$ pyrochlore structure, reside as well at the $B$ site. In such samples ${\mathrm{Yb}}^{3+}$ ions should exist in defective environments at low levels and be subjected to crystalline electric fields very different from those at the stoichiometric $A$ sites. Neutron scattering measurements of ${\mathrm{Yb}}^{3+}$ in four compositions of ${\mathrm{Yb}}_{2+x}{\mathrm{Ti}}_{2\ensuremath{-}x}{\mathrm{O}}_{7\ensuremath{-}y}$ show the spectroscopic signatures for these defective ${\mathrm{Yb}}^{3+}$ ions and explicitly demonstrate that the spin anisotropy of the ${\mathrm{Yb}}^{3+}$ moment changes from $XY$-like for stoichiometric ${\mathrm{Yb}}^{3+}$ to Ising-like for ``stuffed'' $B$ site ${\mathrm{Yb}}^{3+}$ or for $A$ site ${\mathrm{Yb}}^{3+}$ in the presence of oxygen vacancies.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.002 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.003 |
| Insufficient payload (model declined to judge) | 0.304 | 0.050 |
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".