Search results for "GaP"

showing 10 items of 1144 documents

Single-particle properties of the Hubbard model in a novel three-pole approximation

2017

We study the 2D Hubbard model using the Composite Operator Method within a novel three-pole approximation. Motivated by the long-standing experimental puzzle of the single-particle properties of the underdoped cuprates, we include in the operatorial basis, together with the usual Hubbard operators, a field describing the electronic transitions dressed by the nearest-neighbor spin fluctuations, which play a crucial role in the unconventional behavior of the Fermi surface and of the electronic dispersion. Then, we adopt this approximation to study the single-particle properties in the strong coupling regime and find an unexpected behavior of the van Hove singularity that can be seen as a prec…

Hubbard modelSingle-particle propertiesField (physics)Hubbard modelThree-pole approximationVan Hove singularityFOS: Physical sciences02 engineering and technology01 natural sciencesCondensed Matter - Strongly Correlated ElectronsQuantum mechanicsCondensed Matter::Superconductivity0103 physical sciencesCuprateElectrical and Electronic Engineering010306 general physicsSpin-½PhysicsCondensed matter physicsStrongly Correlated Electrons (cond-mat.str-el)Strongly correlated electron systemsFermi surface021001 nanoscience & nanotechnologyCondensed Matter PhysicsComposite Operator MethodElectronic Optical and Magnetic MaterialsComposite Operator Method; Hubbard model; Operatorial approach; Single-particle properties; Strongly correlated electron systems; Three-pole approximation;Operatorial approachStrongly correlated materialCondensed Matter::Strongly Correlated Electrons0210 nano-technologyPseudogap
researchProduct

Custody and Care of Children in Spain: can the Two Rights be Reconciled?

2021

AbstractThis study aims to analyse the legal decision-making process in the Community of Valencia (Spain) regarding contentious divorces particularly with respect to parental authority (patria potestas), custody and visiting arrangements for children, and the opinions of mothers and fathers on the impact these judicial measures have had on their lives. It also considers the biases in these decisions produced by privileging the rights of the adults over those of the children. Three particular moments are studied: (1) the situation before the break-up, focusing on the invisible gender gap in care; (2) the judicial process, where we observe the impact of hidden gender-based violence and gender…

Human rightsmedia_common.quotation_subject050901 criminology05 social sciencesCriminologyPublic international lawGender Studies0501 psychology and cognitive sciencesSociologyGender gapPolitical philosophy0509 other social sciencesMenors050104 developmental & child psychologymedia_common
researchProduct

Engineering the hypersonic phononic band gap of hybrid Bragg stacks.

2012

We report on the full control of phononic band diagrams for periodic stacks of alternating layers of poly(methyl methacrylate) and porous silica combining Brillouin light scattering spectroscopy and theoretical calculations. These structures exhibit large and robust on-axis band gaps determined by the longitudinal sound velocities, densities, and spacing ratio. A facile tuning of the gap width is realized at oblique incidence utilizing the vector nature of the elastic wave propagation. Off-axis propagation involves sagittal waves in the individual layers, allowing access to shear moduli at nanoscale. The full theoretical description discerns the most important features of the hypersonic one…

Hypersonic speedMaterials scienceLightBand gapSuperlatticeBioengineering02 engineering and technology01 natural sciencesOpticsDispersion relation0103 physical sciencesScattering RadiationGeneral Materials ScienceComputer SimulationParticle Size010306 general physicsNanoscopic scaleBrillouin SpectroscopyCondensed matter physicsbusiness.industryMechanical EngineeringGeneral Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsNanostructuresBrillouin zoneShear (sheet metal)RefractometryModels Chemical0210 nano-technologybusinessNano letters
researchProduct

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
researchProduct

ZnO Nanoestructured Layers Processing with Morphology Control by Pulsed Electrodeposition

2011

The fabrication of nanostructured ZnO thin films is a critic process for a lot of applications of this semiconductor material. The final properties of this film depend fundamentally of the morphology of the sintered layer. In this paper a process is presented for the fabrication of ZnO nanostructured layers with morphology control by pulsed electrodeposition over ITO. Process optimization is achieved by pulsed electrodeposition and results are assessed after a careful characterization of both morphology and electrical properties. SEM is used for nucleation analysis on pulsed deposited samples. Optical properties like transmission spectra and Indirect Optical Band Gap are used to evaluate th…

INGENIERIA DE LA CONSTRUCCIONFabricationMaterials scienceBand gapThin-FilmsZinc-OxideNucleationNanotechnologySolar-CellsCrystalline SiliconCIENCIA DE LOS MATERIALES E INGENIERIA METALURGICAMaterials ChemistryElectrochemistryProcess optimizationCrystalline siliconThin filmDepositionDeposition (law)Ciencias ExactasRenewable Energy Sustainability and the Environmentpulsed electrodepositionOptical-PropertiesFísicaCondensed Matter PhysicsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsOxygennanostructured ZnO thin filmsFISICA APLICADALayer (electronics)
researchProduct

ChemInform Abstract: Photoelectrochemical Study of Electrochemically Formed Semiconducting Yttrium Hydride (YH3-x).

2010

Abstract The first photoelectrochemical study of semiconducting YH 3− x films formed by etching bulk Y metal in 0.5 M H 2 SO 4 solution is reported. The formation of semiconducting hydride having an indirect optical band gap, E g opt , of about 2.35 eV is confirmed by in situ photocurrent spectroscopy. The photoelectrochemical behaviour of such a phase was investigated both in alkaline and in acidic solutions. The flat band potential was estimated to be U fb =−1.25 V/NHE, independent of pH.

In situMetalPhotocurrentHydrideBand gapEtching (microfabrication)Chemistryvisual_artPhase (matter)visual_art.visual_art_mediumAnalytical chemistryGeneral MedicineSpectroscopyChemInform
researchProduct

InN thin film lattice dynamics by grazing incidence inelastic x-ray scattering.

2011

Achieving comprehensive information on thin film lattice dynamics so far has eluded well established spectroscopic techniques. We demonstrate here the novel application of grazing incidence inelastic x-ray scattering combined with ab initio calculations to determine the complete elastic stiffness tensor, the acoustic and low-energy optic phonon dispersion relations of thin wurtzite indium nitride films. Indium nitride is an especially relevant example, due to the technological interest for optoelectronic and solar cell applications in combination with other group III nitrides.

Indium nitrideMaterials sciencePhononGeneral Physics and AstronomyPhysics::Optics:Matemàtiques i estadística::Matemàtica discreta::Combinatòria [Àrees temàtiques de la UPC]Nitridechemistry.chemical_compoundCondensed Matter::Materials ScienceWurtzite alnOpticsAb initio quantum chemistry methodsDispersion relationThin filmHexagonal InNPseudopotentialsWurtzite crystal structureCondensed matter physicsbusiness.industryScatteringLattice dynamics:Enginyeria electrònica [Àrees temàtiques de la UPC]Reticles Teoria dechemistryFISICA APLICADAbusinessSpectroscopic techniquesDinàmica reticularFundamental-band gapPhysical review letters
researchProduct

Women’s Job Search Competence: A Question of Motivation, Behavior, or Gender

2018

We examined motivation and behaviors in women's active job search in Spain and the gender gap in this process. The current crisis in Spain and the increase in the number of unemployed people have revealed new inequalities that particularly affect women's employability, especially the most vulnerable women. This paper addresses two exploratory studies: the first study analyzes gender differences in the active job search using a sample of 236 Spanish participants; the second study explores the heterogeneity and diversity of unemployed women in a sample of 235 Spanish women. To analyze the active job search, the respondents were invited to write open-ended responses to questions about their jo…

Inequalitywork-life conciliationmedia_common.quotation_subjectlcsh:BF1-990050109 social psychologyEmployability0502 economics and businessPsychology0501 psychology and cognitive sciencesEmpowermentCompetence (human resources)General PsychologyOriginal Researchmedia_commonGender equality05 social sciencesactive job searchgender gapGeographical Mobilitylcsh:Psychologyunemployment of womenContent analysiswomen’s employabilityGender gapPsychologySocial psychology050203 business & managementFrontiers in Psychology
researchProduct

The gender gap in the diagnostic-therapeutic journey of the infertile couple

2021

Medical procreation impairs both the biological and psychological lives of couples. However, male and female attitudes to infertility are different and require a different approach during the IVF journey. Thus, the gender impact assessment (GIA) method was used to analyse original studies present in the literature. We found some gender-related differences and, subsequently, possible outcomes of intervention to improve healthy reproduction management and prevent infertility. In particular, it became apparent that there was the need for an in-depth male infertility assessment and a gender-specific follow-up.

InfertilityMale2019-20 coronavirus outbreakCoronavirus disease 2019 (COVID-19)Reproductive Techniques AssistedHealth Toxicology and MutagenesisSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)Health StatusGender-oriented specific approachReviewSex FactorMale infertilityHealth Statu03 medical and health sciences0302 clinical medicineSex FactorsSex factorsAssisted reproductive technology (ART)Intervention (counseling)MedicineHumans030212 general & internal medicineInfertility MaleMale infertility030219 obstetrics & reproductive medicinebusiness.industryRPublic Health Environmental and Occupational Healthmedicine.diseaseMedicineFemaleGender gapbusinessClinical psychology
researchProduct

Banking Competition, Collateral Constraints and Optimal Monetary Policy

2013

We analyze optimal monetary policy in a model with two distinct financial frictions. First, borrowing is subject to collateral constraints. Second, credit flows are intermediated by monopolistically competitive banks, thus giving rise to endogenous lending spreads. We show that, up to a second order approximation, welfare maximization is equivalent to stabilization of four goals: inflation, output gap, the consumption gap between constrained and unconstrained agents, and the distribution of the collateralizable asset between both groups. Following both financial and non-financial shocks, the optimal monetary policy commitment implies a short-run trade-off between stabilization goals. Such p…

InflationConsumption (economics)Economics and EconometricsCollateralmedia_common.quotation_subjectMonetary policyjel:E32Maximizationjel:E52Monetary economicsjel:G10jel:G21Competition (economics)Orders of approximationOutput gapAccountingEconomicsAsset (economics)banking competition lending spreads collateral constraints monetary policy linear-quadratic methodWelfareFinancemedia_commonSSRN Electronic Journal
researchProduct