MétaCan
Menu
Back to cohort
Record W2894614846 · doi:10.1021/jacs.8b08753

Origin of Broad Emission Spectra in InP Quantum Dots: Contributions from Structural and Electronic Disorder

2018· article· en· W2894614846 on OpenAlex

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.

fundA Canadian funder is recorded on the work.
no affNo Canadian affiliation: this work is invisible to an affiliation-only frame.
No Canadian affiliation. An affiliation-only frame, the usual design, would never have seen this work. It is one of the works that make the case for inverting the frame.

Bibliographic record

VenueJournal of the American Chemical Society · 2018
Typearticle
Languageen
FieldMaterials Science
TopicQuantum Dots Synthesis And Properties
Canadian institutionsnot available
FundersAir Force Office of Scientific ResearchArgonne National LaboratoryBasic Energy SciencesDivision of ChemistryU.S. Department of EnergyU.S. Department of DefenseDivision of Materials ResearchOffice of ScienceSamsungCanadian Light SourceNational Science Foundation
KeywordsQuantum dotPhotoluminescenceEmission spectrumChemistrySpectral lineSpectroscopyElectronMolecular physicsElectronic structureAbsorption spectroscopyAtomic physicsCondensed matter physicsPhysicsMaterials scienceNanotechnologyOptoelectronicsOptics

Abstract

fetched live from OpenAlex

The ensemble emission spectra of colloidal InP quantum dots are broader than achievable spectra of cadmium- and lead-based quantum dots, despite similar single-particle line widths and significant efforts invested in the improvement of synthetic protocols. We seek to explain the origin of persistently broad ensemble emission spectra of colloidal InP quantum dots by investigating the nature of the electronic states responsible for luminescence. We identify a correlation between red-shifted emission spectra and anomalous broadening of the excitation spectra of luminescent InP colloids, suggesting a trap-associated emission pathway in highly emissive core-shell quantum dots. Time-resolved pump-probe experiments find that electrons are largely untrapped on photoluminescence relevant time scales pointing to emission from recombination of localized holes with free electrons. Two-dimensional electronic spectroscopy on InP quantum dots reveals multiple emissive states and increased electron-phonon coupling associated with hole localization. These localized hole states near the valence band edge are hypothesized to arise from incomplete surface passivation and structural disorder associated with lattice defects. We confirm the presence and effect of lattice disorder by X-ray absorption spectroscopy and Raman scattering measurements. Participation of localized electronic states that are associated with various classes of lattice defects gives rise to phonon-coupled defect related emission. These findings explain the origins of the persistently broad emission spectra of colloidal InP quantum dots and suggest future strategies to narrow ensemble emission lines comparable to what is observed for cadmium-based materials.

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)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.012
Threshold uncertainty score0.300

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.001
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

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.

Opus teacher head0.008
GPT teacher head0.263
Teacher spread0.255 · 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