Search results for "Self assembled"

showing 10 items of 40 documents

Size dependent carrier thermal escape and transfer in bimodally distributed self assembled InAs/GaAs quantum dots

2012

We have investigated the temperature dependent recombination dynamics in two bimodally distributed InAs self assembled quantum dots samples. A rate equations model has been implemented to investigate the thermally activated carrier escape mechanism which changes from exciton-like to uncorrelated electron and hole pairs as the quantum dot size varies. For the smaller dots, we find a hot exciton thermal escape process. We evaluated the thermal transfer process between quantum dots by the quantum dot density and carrier escape properties of both samples. © 2012 American Institute of Physics.

DYNAMICSMaterials scienceAtmospheric escapeCondensed matter physicsExcitonGeneral Physics and AstronomyElectronRate equationThermal transferEPITAXYCondensed Matter::Mesoscopic Systems and Quantum Hall EffectGallium arsenidechemistry.chemical_compoundCondensed Matter::Materials SciencechemistrySTATESself assembled quantum dots rate equations model carrier escape propertiesQuantum dotQuantum dot laserLUMINESCENCEPHOTOLUMINESCENCE
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Halogen bond directionality translates tecton geometry into self-assembled architecture geometry

2013

The structures of halogen-bonded infinite chains involving two diiodoperfluoroalkanes and a bent bis(pyrid-4′-yl)oxadiazole show that the geometry of the pyridyl pendant rings is translated into the angle between the formed halogen bonds.

Halogen bondhalogen bond self-assemblyBent molecular geometryOxadiazoleGeometryGeneral ChemistrySettore CHIM/06 - Chimica OrganicaCondensed Matter PhysicsSelf assembledchemistry.chemical_compoundchemistryHalogenDirectionalityGeneral Materials Science
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Self-Assembled Hydrogen-Bonded Dimeric Capsules with High Kinetic Stability

2000

HydrogenComputational chemistryHydrogen bondChemistryCalixareneKineticsOrganic chemistrychemistry.chemical_elementGeneral ChemistryKinetic energyHost–guest chemistryCatalysisSelf assembledAngewandte Chemie International Edition
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Oscillator strength reduction induced by external electric fields in self-assembled quantum dots and rings

2007

We have carried out continuous wave and time resolved photoluminescence experiments in self-assembled In(Ga)As quantum dots and quantum rings embedded in field effect structure devices. In both kinds of nanostructures, we find a noticeable increase of the exciton radiative lifetime with the external voltage bias that must be attributed to the field-induced polarizability of the confined electron hole pair. The interplay between the exciton radiative recombination and the electronic carrier tunneling in the presence of a stationary electric field is therefore investigated and compared with a numerical calculation based on the effective mass approximation.

III-V semiconductorsOscillator strengthRadiative lifetimesTime resolved spectraTunnellingSelf assembledCondensed Matter::Materials ScienceGallium arsenideIndium compoundsElectric fieldQuantum mechanicsSemiconductor quantum dotsNetwork of excellenceEuropean commissionPhotoluminescenceQuantum tunnellingPhysicsSelf-assemblyCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsQuantum dotEffective massElectron hole recombinationElectron-hole recombinationPhysical Review B
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Self-Assembled Zinc Oxide Quantum Dots Using Spray Pyrolysis Methodology

2011

Self-assembled ZnO quantum dots (QDs) have been obtained on different substrates by using the atmospheric spray pyrolysis methodology under well-defined growth conditions. The evolution of size and...

Materials scienceCondensed Matter::OtherInorganic chemistrychemistry.chemical_elementGeneral ChemistryZincCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter PhysicsSpray pyrolysisSelf assembledCondensed Matter::Materials SciencechemistryChemical engineeringQuantum dotPhysics::Atomic and Molecular ClustersGeneral Materials ScienceCrystal Growth & Design
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Self-Assembled Hydrogen Bonded Dimers of Calix[4]arenes

1998

Self-assembly of suitably functionalized molecules to well defined supramolecular structures has become a topic of current interest. Various molecules have been designed which are able to mimic in part the recognition and self-organisation processes which are found as a general principle in nature.[1]

Materials scienceHydrogenchemistrySupramolecular chemistrychemistry.chemical_elementMoleculePhotochemistryCombinatorial chemistrySelf assembled
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Size self-filtering effect in vertical stacks of InAs/InP self-assembled quantum wires

2003

3 páginas, 2 figuras.-- PACS: 73.21.Hb; 78.55.Cr; 78.67.Lt.-- Proceedings of the International Conference on Superlattices, Nano-structures and Nano-devices ICSNN 2002.

Materials sciencePhotoluminescenceCondensed matter physicsbusiness.industryQuantum wiresPhysics::OpticsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter PhysicsLayer thicknessAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsSelf assembledCondensed Matter::Materials ScienceHomogeneity (physics)Physics::Accelerator PhysicsOptoelectronicsVertical stacksbusinessQuantumPhotoluminescenceMolecular beam epitaxy
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Self-assembled FeCo/gelatin nanospheres with rapid magnetic response and high biomolecule-loading capacity.

2009

Materials sciencefood.ingredientTime FactorsIronNanoparticleNanotechnologyGelatinSelf assembledBiomaterialsMagneticsfoodAnimalsGeneral Materials Sciencechemistry.chemical_classificationBiomoleculeGeneral ChemistryMagnetic responseCobaltDNAchemistryDrug deliveryThermogravimetryGelatinSelf-assemblyNanospheresBiotechnologySmall (Weinheim an der Bergstrasse, Germany)
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Self-assembled metal-oxide nanoparticles on GaAs: infrared absorption enabled by localized surface plasmons

2021

Abstract Metal-oxides hold promise as superior plasmonic materials in the mid-infrared compared to metals, although their integration over established material technologies still remains challenging. We demonstrate localized surface plasmons in self-assembled, hemispherical CdZnO metal-oxide nanoparticles on GaAs, as a route to enhance the absorption in mid-infrared photodetectors. In this system, two localized surface plasmon modes are identified at 5.3 and 2.7 μm, which yield an enhancement of the light intensity in the underlying GaAs. In the case of the long-wavelength mode the enhancement is as large as 100 near the interface, and persists at depths down to 50 nm. We show numerically t…

Materials sciencequantum wellQC1-999Infrared spectroscopy02 engineering and technologyMetal oxide nanoparticles01 natural sciencesSelf assembledmetal-oxide0103 physical sciencesElectrical and Electronic Engineeringintersubband transition010306 general physicsQuantum wellcdolocalized surface plasmonbusiness.industryPhysics021001 nanoscience & nanotechnologyCondensed Matter::Mesoscopic Systems and Quantum Hall EffectAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsOptoelectronics0210 nano-technologybusinessBiotechnologyLocalized surface plasmonNanophotonics
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Recent developments in dipyrrin based metal complexes: Self-assembled nanoarchitectures and materials applications

2020

While dipyrrin-boron complexes (BODIPYs) and their derivatives have attracted much attention, dipyrrin-based metal complexes recently appeared as a novel luminescent material. So far, dipyrrin-metal complexes have been regarded as non-luminescent or weakly luminescent. Interestingly, introduction of steric hindrance at the meso-position and the development of heteroleptic complexes with proper frontier orbital ordering are two recent strategies that have been developed to improve their luminescent ability. Compared with BODIPYs, one of the distinctive advantages of dipyrrin-metal complexes is that they can form a series of self-assembled supramolecules and polymer assemblies via facile coo…

MetalChemistryvisual_artLuminescent materialvisual_art.visual_art_mediumNanotechnologyGeneral ChemistrySelf assembledJournal of Porphyrins and Phthalocyanines
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