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Record W2083007696 · doi:10.1103/physrevb.61.15338

Evidence of ferromagnetically coupled<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi mathvariant="normal">Nd</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>ion pairs in weakly doped<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">N</mml:mi><mml:mi mathvariant="normal">d</mml:mi><mml:mo>:</mml:mo><mml:mi mathvariant="normal">L</mml:mi><mml:mi mathvariant="normal">i</mml:mi><mml:mi mathvariant="normal">Y</mml:mi><mml:mi mathvariant="normal">F</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">N</mml:mi><mml:mi mathvariant="normal">d</mml:mi><mml:mo>:</mml:mo><mml:mi mathvariant="normal">Y</mml:mi><mml:mi mathvariant="normal">V</mml:mi><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>crystals as revealed by high-resolution optical and EPR spectroscopies

2000· article· lv· W2083007696 on OpenAlex
O. Guillot-Noël, V. Mehta, Bruno Viana, Didier Gourier, M. Boukhris, S. Jandl

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenuePhysical review. B, Condensed matter · 2000
Typearticle
Languagelv
FieldMaterials Science
TopicLuminescence Properties of Advanced Materials
Canadian institutionsUniversité de Sherbrooke
Fundersnot available
KeywordsPhysicsElectron paramagnetic resonanceIonNeodymiumCrystallographySpectral lineAtomic physicsNuclear magnetic resonanceChemistryOpticsQuantum mechanics

Abstract

fetched live from OpenAlex

Electron paramagnetic resonance (EPR) and high-resolution fluorescence spectra of ${\mathrm{Nd}}^{3+}$ ions in weakly doped ${\mathrm{LiYF}}_{4}$ and ${\mathrm{YVO}}_{4}$ crystals are analyzed. A simple model, based on an effective spin-Hamiltonian approach is proposed to explain the general features of the EPR and optical neodymium spectra in these matrices. Pairs of satellite lines whose intensities grow with neodymium content are observed on each side of the main EPR signals of isolated ${\mathrm{Nd}}^{3+}$ ions. These satellites are assigned to ${\mathrm{Nd}}^{3+}{\ensuremath{-}\mathrm{N}\mathrm{d}}^{3+}$ ion pairs coupled by magnetic dipolar interaction. The calculated Nd-Nd distances are found to be in good agreement with the ${\mathrm{Y}}^{3+}{\ensuremath{-}\mathrm{Y}}^{3+}$ distances in ${\mathrm{LiYF}}_{4}$ and ${\mathrm{YVO}}_{4}$ hosts. The concentration-dependent satellites accompanying the neodymium ${}^{4}{\stackrel{\ensuremath{\rightarrow}}{{F}_{3/2}}}^{4}{I}_{9/2}$ transition are quantitatively explained as being due to several types of ferromagnetically coupled pairs of ${\mathrm{Nd}}^{3+}$ ions, each ion of a pair being located at the regular ${\mathrm{Y}}^{3+}$ site with ${S}_{4}$ and ${D}_{2d}$ point symmetry in ${\mathrm{LiYF}}_{4}$ and ${\mathrm{YVO}}_{4},$ respectively. The exchange coupling values J are found in the range +0.8 to +4.9 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. From literature data, it appears that such ferromagnetically coupled ${\mathrm{Nd}}^{3+}$ pairs with $J=+3{\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ also quantitatively explain the optical satellite structure in ${\mathrm{N}\mathrm{d}:\mathrm{Y}}_{3}{\mathrm{Al}}_{5}{\mathrm{O}}_{12}$ (YAG).

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.013
metaresearch head score (Gemma)0.010
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesMetaresearch, Meta-epidemiology (narrow), Science and technology studies, Scholarly communication, Open science, Research integrity, Insufficient payload (model declined to judge)
Consensus categoriesMeta-epidemiology (narrow), Science and technology studies, Open science, Research integrity, Insufficient payload (model declined to judge)
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: none
Teacher disagreement score0.868
Threshold uncertainty score0.998

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0130.010
Meta-epidemiology (narrow)0.0060.012
Meta-epidemiology (broad)0.0020.009
Bibliometrics0.0040.007
Science and technology studies0.0090.011
Scholarly communication0.0110.013
Open science0.0140.014
Research integrity0.0130.010
Insufficient payload (model declined to judge)0.8830.015

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.

Opus teacher head0.015
GPT teacher head0.246
Teacher spread0.231 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it