Search results for "NITRIDES"

showing 3 items of 13 documents

Blue lasing at room temperature in high quality factor GaN/AlInN microdisks with InGaN quantum wells

2007

The authors report on the achievement of optically pumped III-V nitride blue microdisk lasers operating at room temperature. Controlled wet chemical etching of an AlInN interlayer lattice matched to GaN allows forming inverted cone pedestals. Whispering gallery modes are observed in the photoluminescence spectra of InGaN/GaN quantum wells embedded in the GaN microdisks. Typical quality factors of several thousands are found (Q>4000). Laser action at similar to 420 nm is achieved under pulsed excitation at room temperature for a peak power density of 400 kW/cm(2). The lasing emission linewidth is down to 0.033 nm.

PhotoluminescenceMaterials sciencePhysics and Astronomy (miscellaneous)business.industryBOXESSettore ING-INF/01 - ElettronicaSemiconductor laser theoryGANOptical pumpingMICROCAVITIESLaser linewidthOpticsLASERSSemiconductors Laser physics Photoluminescence spectroscopy Oscillator strengths Quantum wells Optical absorption Whispering gallery wave Nitrides Etching Electrical properties and parametersOptoelectronicsStimulated emissionWhispering-gallery waveGAAS MICRODISKSbusinessLasing thresholdQuantum well
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Evolution of the microstructure of sputter deposited TaAlON thin films with increasing oxygen partial pressure

2021

Recently, quaternary oxynitrides of transition metals and aluminum have attracted increasing interest due to their tunable properties. Within the present work, a series of TaAl(O)N films was sputter deposited using constant nitrogen and varying oxygen partial pressures. The films were grown from single element Ta and Al targets. The deposition parameters were adjusted to obtain a Ta/Al atomic ratio of ~50/50 for the oxygen-free film and were held constant for the following depositions, with the exception of the increasing oxygen partial pressure and compensatory decreasing argon partial pressure. Elastic recoil detection analysis revealed oxygen contents of up to ~26 at.%, while the nitroge…

mikrorakenteetTaAlONmicrostructureoxynitridesTEMXPSpinnoitusohutkalvot
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SrP3N5O: a highly condensed layer phosphate structure solved from a nanocrystal by automated electron diffraction tomography.

2011

The oxonitridophosphate SrP(3)N(5)O has been synthesized by heating a multicomponent reactant mixture that consisted of phosphoryl triamide OP(NH(2))(3), thiophosphoryl triamide SP(NH(2))(3), SrS, and NH(4)Cl enclosed in evacuated and sealed silica-glass ampoules up to 750 °C. The compound was obtained as nanocrystalline powder with needle-shaped crystallites. The crystal structure was solved ab initio on the basis of electron diffraction data by means of automated electron diffraction tomography (ADT) and verified by Rietveld refinement with X-ray powder diffraction data. SrP(3)N(5)O crystallizes in the orthorhombic space group Pnma (no. 62) with unit-cell data of a=18.331(2), b=8.086(1), …

phosphatesRietveld refinementChemistryOrganic ChemistryAb initioGeneral ChemistryCrystal structureelectron diffraction; layered compounds; oxonitrides; phosphates; strontiumoxonitridesCatalysisNMR spectra databaseCrystallographyElectron diffractionlayered compoundselectron diffractionOrthorhombic crystal systemCrystallitestrontiumPowder diffractionChemistry (Weinheim an der Bergstrasse, Germany)
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