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Bibliographic record
Abstract
The Ferrell-Glover-Tinkham (FGT) sum rule has been applied to the temperature dependence of the in-plane optical conductivity of optimally doped ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.95}$ and underdoped ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.60}.$ Within the accuracy of the experiment, the sum rule is obeyed in both materials. However, the energy scale ${\ensuremath{\omega}}_{c}$ required to recover the full strength of the superfluid ${\ensuremath{\rho}}_{s}$ in the two materials is dramatically different; ${\ensuremath{\omega}}_{c}\ensuremath{\simeq}800{\mathrm{cm}}^{\ensuremath{-}1}$ in the optimally doped system (close to twice the maximum of the superconducting gap $2{\ensuremath{\Delta}}_{0}),$ but ${\ensuremath{\omega}}_{c}\ensuremath{\gtrsim}5000{\mathrm{cm}}^{\ensuremath{-}1}$ in the underdoped system. In both materials, the normal-state scattering rate close to the critical temperature is small, $\ensuremath{\Gamma}<2{\ensuremath{\Delta}}_{0},$ so that the materials are not in the dirty limit and the relevant energy scale for ${\ensuremath{\rho}}_{s}$ in a BCS material should be twice the energy gap. The FGT sum rule in the optimally doped material suggests that the majority of the spectral weight of the condensate comes from energies below $2{\ensuremath{\Delta}}_{0},$ which is consistent with a BCS material in which the condensate originates from a Fermi-liquid normal state. In the underdoped material the larger energy scale may be a result of the non-Fermi-liquid nature of the normal state. The dramatically different energy scales suggest that the nature of the normal state creates specific conditions for observing the different aspects of what is presumably a central mechanism for superconductivity in these materials.
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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 | 0.008 | 0.006 |
| Meta-epidemiology (narrow) | 0.004 | 0.010 |
| Meta-epidemiology (broad) | 0.002 | 0.009 |
| Bibliometrics | 0.003 | 0.007 |
| Science and technology studies | 0.007 | 0.009 |
| Scholarly communication | 0.008 | 0.010 |
| Open science | 0.011 | 0.010 |
| Research integrity | 0.009 | 0.009 |
| Insufficient payload (model declined to judge) | 0.970 | 0.008 |
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; both teacher heads agree on what is shown here.
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".