Search results for "Reflection high-energy electron diffraction"

showing 5 items of 35 documents

Morphology and magnetoresistance of Co2Cr0.6Fe0.4Al-based tunnelling junctions

2009

Some ferromagnetic Heusler compounds are theoretically predicted to be half metallic materials, i.e. to be characterized by a huge spin polarization at the Fermi energy. We investigate the correlations between junction preparation conditions, morphology and transport properties of planar MgO/Co2Cr0.6Fe0.4Al/AlOx/Co/CoOx/Pt tunnelling junctions. Epitaxial Co2Cr0.6Fe0.4Al thin films were deposited by dc and rf magnetron sputtering on different buffer layers (Cr, Fe, MgO) on MgO(1 0 0) substrates. By RHEED, LEED and in situ STM investigations different surface morphologies were observed. Atomically flat surfaces with Co2Cr0.6Fe0.4Al unit cell sized steps (B2 structure) were obtained by rf sput…

Reflection high-energy electron diffractionMaterials scienceAcoustics and UltrasonicsCondensed matter physicsMetallurgySputter depositionCondensed Matter PhysicsEpitaxySurfaces Coatings and FilmsElectronic Optical and Magnetic Materialslaw.inventionTunnel magnetoresistancelawSputteringScanning tunneling microscopeThin filmQuantum tunnellingJournal of Physics D: Applied Physics
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Electron Diffraction Reinvestigation of CdCr<sub>2</sub>Se<sub>4</sub> and ZnCr<sub>2-x</sub>V<sub>x</su…

2013

Crystal structure of two spinel single crystals CdCr2Se4 and ZnCr2-xVxSe4 have been reinvestigated using automated electron diffraction tomography method with beam precession. 3D reciprocal space have been reconstructed base on recorded tilt series. For both samples crystal structure was refined and the cubic symmetry with space group Fd-3m was confirmed. No additional electron potential has been located beside occupied atom sites.

Reflection high-energy electron diffractionMaterials scienceGas electron diffractionSpinelCrystal structureengineering.materialCondensed Matter PhysicsAtomic and Molecular Physics and OpticsCrystallographyElectron diffractionengineeringPrecession electron diffractionGeneral Materials SciencePowder diffractionElectron backscatter diffractionSolid State Phenomena
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Ex situ investigations of MOCVD-grown gallium nitride nanowires using reflection high energy electron diffraction

2011

Vertically oriented nanowires (NWs) of single-crystalline wurtzite GaN have been fabricated on sapphire substrates, via metal organic chemical vapor deposition (MOCVD). We present ex situ investigations on orientation and structure of grown GaN nanowires on GaN(0001) surface using reflection high energy electron diffraction (RHEED). Both ordered and randomly oriented GaN crystalline structures have been detected.

Reflection high-energy electron diffractionMaterials sciencebusiness.industryNanowireGallium nitrideChemical vapor depositionCrystallographychemistry.chemical_compoundchemistryElectron diffractionSapphireOptoelectronicsMetalorganic vapour phase epitaxybusinessWurtzite crystal structureIOP Conference Series: Materials Science and Engineering
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Isolated self-assembled InAs/InP(001) quantum wires obtained by controlling the growth front evolution

2007

6 páginas, 5 figuras. In this work we explore the first stages of quantum wire (QWR) formation studying the evolution of the growth front for InAs coverages below the critical thickness, θc, determined by reflection high energy electron diffraction (RHEED). Our results obtained by in situ measurement of the accumulated stress evolution during InAs growth on InP(001) show that the relaxation process starts at a certain InAs coverage θRθR this ensemble of isolated nanostructures progressively evolves towards QWRs that cover the whole surface for θ = θc. These results allow for a better understanding of the self-assembling process of QWRs and enable the study of the individual properties of In…

Single quantum wiresWork (thermodynamics)Materials scienceNanostructureReflection high-energy electron diffractionCondensed matter physicsMechanical EngineeringQuantum wireBioengineeringGeneral ChemistryCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter::Materials ScienceCrystallographyReflection (mathematics)Electron diffractionMechanics of MaterialsGeneral Materials ScienceElectrical and Electronic EngineeringMolecular beam epitaxyQuantumMolecular beam epitaxyNanotechnology
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Microstructure of a Discotic Polymer as Revealed by Electron Diffraction and High-Resolution Imaging

1989

chemistry.chemical_classificationReflection high-energy electron diffractionMaterials scienceAnalytical chemistryGeneral MedicineGeneral ChemistryPolymerMicrostructureCatalysisCrystallographychemistryElectron diffractionHigh resolution imagingElectron backscatter diffractionAngewandte Chemie International Edition in English
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