Search results for "Interface states"

showing 5 items of 5 documents

Thin film growth and band lineup of In2O3 on the layered semiconductor InSe

1999

Thin films of the transparent conducting oxide In2O3 have been prepared in ultrahigh vacuum by reactive evaporation of indium. X-ray diffraction, optical, and electrical measurements were used to characterize properties of films deposited on transparent insulating mica substrates under variation of the oxygen pressure. Photoelectron spectroscopy was used to investigate in situ the interface formation between In2O3 and the layered semiconductor InSe. For thick In2O3 films a work function of φ = 4.3 eV and a surface Fermi level position of EF−EV = 3.0 eV is determined, giving an ionization potential IP = 7.3 eV and an electron affinity χ = 3.7 eV. The interface exhibits a type I band alignmen…

Materials scienceAnalytical chemistryIonisation potentialGeneral Physics and AstronomyWork functionPhotoelectron spectrasymbols.namesakeX-ray photoelectron spectroscopyIndium compounds:FÍSICA [UNESCO]Electron affinityWork functionThin filmbusiness.industryFermi levelUNESCO::FÍSICAHeterojunctionInterface statesBand structureEvaporation (deposition)X-ray diffractionElectron affinitySemiconductorVacuum depositionIndium compounds ; Vacuum deposition ; X-ray diffraction ; Photoelectron spectra ; Semiconductor-insulator boundaries ; Work function ; Fermi level ; Ionisation potential ; Electron affinity ; Interface states ; Band structureFermi levelsymbolsSemiconductor-insulator boundariesOptoelectronicsbusiness
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Correlation between optical properties and barrier composition in InxGa1−xP/GaAs quantum wells

1998

9 páginas, 11 figuras.

III-V semiconductorsPhotoluminescenceMaterials scienceBand gapExcitonAlloyGeneral Physics and Astronomyengineering.materialGallium arsenideSpectral line broadeningchemistry.chemical_compoundCondensed Matter::Materials ScienceGallium arsenideIndium compounds:FÍSICA [UNESCO]Optical constantsInterface structureFluctuationsSemiconductor quantum wellsPhotoluminescenceQuantum wellCondensed matter physicsCondensed Matter::OtherGallium compoundsUNESCO::FÍSICAHeterojunctionInterface statesCondensed Matter::Mesoscopic Systems and Quantum Hall EffectStoichiometryEnergy gapchemistryIndium compounds ; Gallium compounds ; III-V semiconductors ; Gallium arsenide ; Semiconductor quantum wells ; Interface structure ; Photoluminescence ; Excitons ; Interface states ; Fluctuations ; Stoichiometry ; Spectral line broadening ; Energy gap ; Optical constantsengineeringExcitonsMolecular beam epitaxy
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Colloidal Nanoplatelet/Conducting Polymer Hybrids: Excitonic And Material Properties

2016

WOS:000370678700053 Here we present the first account of conductive polymer/colloidal nanoplatelet hybrids. For this, we developed DEH-PPV-based polymers with two different anchor groups (sulfide and amine) acting as surfactants for CdSe nanoplatelets, which are atomically flat semiconductor nanocrystals. Hybridization of the polymers with the nanoplatelets in the solution phase was observed to cause strong photoluminescence quenching in both materials. Through steady-state photoluminescence and excitation spectrum measurements, photoluminescence quenching was shown to result from dominant exciton dissociation through charge transfer at the polymer/nanoplatelet interfaces that possess a sta…

Excitation spectrumMaterials sciencePhotoluminescenceSulfideDEH-PPV-Based PolymersSulfideExcitonCdSe NanoplateletsNanotechnology02 engineering and technologySurface active agents010402 general chemistryOptoelectronic devices01 natural sciencesDissociation (chemistry)ColloidCharge transferQuenchingHybrid optoelectronic devicesPhysical and Theoretical ChemistryPhotoluminescenceSulfur compoundsAmineSemiconductor nanocrystalsConductive polymerchemistry.chemical_classificationExcited statesBuilding blockesPolymerInterface statesEmission quenching021001 nanoscience & nanotechnology0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsPolymer/Colloidal Nanoplatelet HybridsGeneral EnergyChemical engineeringchemistryExcited stateAnchorsExcitons0210 nano-technologyDissociationConductive polymerPhotoluminescence quenchingExciton dissociation
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Residual strain effects on the two-dimensional electron gas concentration of AlGaN/GaN heterostructures

2001

Ga-face AlGaN/GaN heterostructures with different sheet carrier concentrations have been studied by photoluminescence and Raman spectroscopy. Compared to bulk GaN, an energy shift of the excitonic emission lines towards higher energies was observed, indicating the presence of residual compressive strain in the GaN layer. This strain was confirmed by the shift of the E2 Raman line, from which biaxial compressive stresses ranging between 0.34 and 1.7 GPa were deduced. The spontaneous and piezoelectric polarizations for each layer of the heterostructures have been also calculated. The analysis of these quantities clarified the influence of the residual stress on the sheet electron concentratio…

Electron densityTwo-dimensional electron gasMaterials sciencePhotoluminescenceIII-V semiconductorsAluminium compounds ; Gallium compounds ; III-V semiconductors ; Wide band gap semiconductors ; Semiconductor heterojunctions ; Two-dimensional electron gas ; Electron density ; Internal stresses ; Photoluminescence ; Raman spectra ; Excitons ; Interface states ; Piezoelectric semiconductors ; Dielectric polarisationExcitonAnalytical chemistryGeneral Physics and AstronomyDielectric polarisationMolecular physicsCondensed Matter::Materials Sciencesymbols.namesakeResidual stress:FÍSICA [UNESCO]Emission spectrumPiezoelectric semiconductorsPhotoluminescenceAluminium compoundsUNESCO::FÍSICAWide-bandgap semiconductorGallium compoundsHeterojunctionInterface statesWide band gap semiconductorssymbolsExcitonsRaman spectraSemiconductor heterojunctionsRaman spectroscopyInternal stressesElectron density
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Optical transitions and excitonic recombination in InAs/InP self-assembled quantum wires

2001

InAs self-assembled quantum wire structures have been grown on InP substrates and studied by means of photoluminescence and polarized-light absorption measurements. According to our calculations, the observed optical transitions in each sample are consistent with wires of different heights, namely from 6 to 13 monolayers. The nonradiative mechanism limiting the emission intensity at room temperature is related to thermal escape of carriers out of the wires.

PhotoluminescenceIII-V semiconductorsPhysics and Astronomy (miscellaneous)ExcitonCondensed Matter::Materials ScienceIndium compoundsMonolayerLight absorptionAbsorption (electromagnetic radiation)QuantumPhotoluminescencePhysicsAtmospheric escapebusiness.industryQuantum wireSelf-assemblyInterface statesCondensed Matter::Mesoscopic Systems and Quantum Hall EffectLight polarisationSemiconductor quantum wiresOptoelectronicsExcitonsSelf-assemblyNonradiative transitionsbusiness
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