Search results for "campi elettromagnetici"

showing 10 items of 155 documents

NEAR INFRARED PICOSECOND PULSED BACKWARD SECOND-HARMONIC-GENERATION IN PERIODICALLY-POLED LITHIUM NIOBATE

2011

We report on backward second-harmonic-generation in bulk periodically-poled congruent lithium niobate with a 3.2μm period. A picosecond pulsed laser allowed us exciting a resonance at 1722nm. The resonances were also resolved by temperature tuning.

Lithium NiobatePeriodically-poled congruent lithium niobateSettore ING-INF/02 - Campi ElettromagneticiBackward second-harmonic-generationSettore ING-INF/01 - Elettronica
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Radar Imager for Mars’ Subsurface Exploration (RIMFAX)

2022

In questo articolo viene illustrato il principio di funzionamento del (RIMFAX) della missione NASA MARS 2020. A seguire, viene presentato il progetto di una antenna Vivaldi (UWB) in sostituzione della Bowtie

MARSVivaldiSettore ING-INF/02 - Campi ElettromagneticiRIMFAXSettore ING-INF/01 - Elettronica
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Graded Carrier Concentration Absorber Profile for High Efficiency CIGS Solar Cells

2015

We demonstrate an innovative CIGS-based solar cells model with a graded doping concentration absorber profile, capable of achieving high efficiency values. In detail, we start with an in-depth discussion concerning the parametrical study of conventional CIGS solar cells structures. We have used the wxAMPS software in order to numerically simulate cell electrical behaviour. By means of simulations, we have studied the variation of relevant physical and chemical parameters-characteristic of such devices-with changing energy gap and doping density of the absorber layer. Our results show that, in uniform CIGS cell, the efficiency, the open circuit voltage, and short circuit current heavily depe…

Materials scienceArticle SubjectBand gaplcsh:TJ807-830lcsh:Renewable energy sourceschemistry.chemical_elementSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciSettore ING-INF/01 - ElettronicaTHIN-FILMSOpticsGeneral Materials ScienceCU(INGA)SE-2Renewable Energy Sustainability and the Environmentbusiness.industryOpen-circuit voltageDopingSettore ING-INF/02 - Campi ElettromagneticiGeneral ChemistryCopper indium gallium selenide solar cellsAtomic and Molecular Physics and OpticschemistryLAYERMolybdenumOptoelectronicsbusinessPhotovoltaicShort circuitLayer (electronics)International Journal of Photoenergy
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RFID epidermal sensor including hydrogel membranes for wound monitoring and healing

2015

This contribution experimentally demonstrates for the first time the feasibility of joint application of passive UHF RFID technology and hydrogel membranes to fabricate smart plasters able to gather and remotely transmit information on the conditions of human skin. In particular, this intelligent plaster is sensitive to temperature and fluid uptake/release and could open interesting scenarios in wound healing monitoring and drug delivery.

Materials scienceComputer Networks and CommunicationsRFID sensortechnology industry and agriculturesmart plasterSettore ING-INF/02 - Campi ElettromagneticiWound monitoringepidermal electronics; hydrogel; RFID sensor; smart plaster; would healing;epidermal electronicDrug deliveryHydrogel membraneepidermal electronicsElectrical and Electronic Engineeringhydrogelwould healingBiomedical engineering
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Design and realization of a portable multichannel continuous wave fNIRS

2014

A design and implementation of a portable functional Near InfraRed Spectroscopy embedded system prototype is described. In this theoretical and experimental work, we present an embedded system hosting 64 LED sources and 128 Silicon PhotoMultiplier detectors (SiPM). The elementary part of the structure is a flexible probe “leaf” consisting of 16 SiPMs, 4 couples of LEDs, each operating at two wavelengths, and a temperature sensor. The hardware system is based on an ARM main microcontroller that allows to perform both the switching time of LEDs and the acquisition of the SiPM outputs. The performed preliminary experimental tests achieved very promising results, thus demonstrating the effectiv…

Materials scienceDetectorSettore ING-INF/02 - Campi ElettromagneticiSettore ING-INF/01 - ElettronicaSilicon PhotoMultiplierlaw.inventionSwitching timeembedded systemMicrocontrollerSilicon photomultiplierlawElectronic engineeringFunctional Near Infrared SpectroscopyFunctional near-infrared spectroscopyContinuous wavephotodetectorRealization (systems)Light-emitting diode2014 AEIT Annual Conference - From Research to Industry: The Need for a More Effective Technology Transfer (AEIT)
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Features of randomized electric-field assisted domain inversion in lithium tantalate

2011

We report on bulk and guided-wave second-harmonic generation via random Quasi-Phase-Matching in Lithium Tantalate. By acquiring the far-field profiles at several wavelengths, we extract statistical information on the distribution of the quadratic nonlinearity as well as its average period, both at the surface and in the bulk of the sample. By investigating the distribution in the two regions we demonstrate a non-invasive approach to the study of poling dynamics.

Materials scienceLightNonlinear opticFOS: Physical sciencesTantalumLithiumSettore ING-INF/01 - Elettronicachemistry.chemical_compoundElectromagnetic FieldsElectric fieldScattering RadiationComputer SimulationQuadratic nonlinearityPolingSettore ING-INF/02 - Campi ElettromagneticiOxidesInversion (meteorology)Equipment DesignModels TheoreticalHarmonic generation and mixingAtomic and Molecular Physics and OpticsComputational physicsEquipment Failure AnalysisRefractometryWavelengthchemistryLithium tantalateComputer-Aided DesignOptics (physics.optics)Physics - Optics
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Parametrical study of multilayer structures for CIGS solar cells

2014

In this paper, a numerical analysis of relevant electrical parameters of multilayer structures for CIGS-based solar cells was carried out, employing the simulation software wxAMPS. In particular, we have focused on thin film cells having a ZnO:Al/ZnO/CdS/CIGS structure with a Molybdenum back contact. The aim of this work is to establish good theoretical reference values for an ongoing experimental activity, where our technology of choice is the single-step electrodeposition. In detail, we have analyzed how the main electrical properties change with the bang gap and the thickness of the absorber layer, for such a type of solar cell structure. Our results show that both efficiency and fill fa…

Materials scienceOrganic solar cellbusiness.industryBand gapSolar cellSettore ING-INF/02 - Campi ElettromagneticiHybrid solar cellCIGSQuantum dot solar cellSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciCopper indium gallium selenide solar cellsSettore ING-INF/01 - ElettronicaPolymer solar celllaw.inventionthin-filmlawSolar cellElectronic engineeringOptoelectronicsPlasmonic solar cellSettore CHIM/07 - Fondamenti Chimici Delle Tecnologiesingle-step electrodeposition.business
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PPG embedded system for blood pressure monitoring

2014

In this work, we have designed and implemented a microcontroller-based embedded system for blood pressure monitoring through a PhotoPlethysmoGraphic (PPG) technique. In our system, it is possible to perform PPG measurements via reflectance mode. Hardware novelty of our system consists in the adoption of Silicon PhotoMultiplier detectors. The signal received from the photodetector is used to calculate the instantaneous heart rate and therefore the heart rate variability. The obtained results show that, by using our system, it is possible to easily extract both the PPG and the breath signal. These signals can be used to monitor the patients during the convalescence both in hospital and at hom…

Materials scienceSettore INF/01 - InformaticaPhotoPlethysmoGraphybusiness.industryDetectorPhotodetectorSettore ING-INF/02 - Campi ElettromagneticiSignalReflectivitySilicon PhotoMultiplierembedded systemMicrocontrollerSilicon photomultipliersensorEmbedded systemHeart rate variabilityBlood pressure monitoringsense organsbusinessComputer hardware2014 AEIT Annual Conference - From Research to Industry: The Need for a More Effective Technology Transfer (AEIT)
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Parametric conversion in micrometer and sub-micrometer structured ferroelectric crystals by surface poling

2012

We report on recent technological improvements concerning nonlinear patterning of lithium niobate and lithium tantalate in the micrometer and submicrometer scales using surface periodic poling for ferroelectric domain inversion. The fabricated samples were employed for frequency doubling via quasiphase-matching both in bulk and guided wave geometries, including forward and backward configurations and wavelength conversion in bands C and L. We also investigated short-period quasiperiodic samples with randomly distributed mark-to-space ratios.

Materials scienceSurface PolingLithium niobatePhysics::OpticsSettore ING-INF/01 - ElettronicaFerroelectric Crystalchemistry.chemical_compoundOpticsPeriodic polinglcsh:QC350-467Parametric ConversionupconversionGuided wave testingbusiness.industryPolingparametric generationferroelectricsSettore ING-INF/02 - Campi ElettromagneticiFerroelectricityAtomic and Molecular Physics and OpticsPhoton upconversionElectronic Optical and Magnetic MaterialschemistryQuasiperiodic functionLithium tantalatebusinesslcsh:Optics. Light
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Tuning the Ultrafast Response of Fano Resonances in Halide Perovskite Nanoparticles

2020

International audience; The full control of the fundamental photophysics of nanosystems at frequencies as high as few THz is key for tunable and ultrafast nanophotonic devices and metamaterials. Here we combine geometrical and ultrafast control of the optical properties of halide perovskite nanoparticles, which constitute a prominent platform for nanophotonics. The pulsed photoinjection of free carriers across the semiconducting gap leads to a subpicosecond modification of the far-field electromagnetic properties that is fully controlled by the geometry of the system. When the nanoparticle size is tuned so as to achieve the overlap between the narrowband excitons and the geometry-controlled…

Materials scienceTerahertz radiationNanophotonicsFOS: Physical sciencesGeneral Physics and AstronomyPhysics::Optics02 engineering and technology010402 general chemistrySettore FIS/03 - FISICA DELLA MATERIA01 natural sciencesOptical switchhalide perovskites nanoparticles[SPI]Engineering Sciences [physics]Fano resonance; halide perovskites nanoparticles; ultrafast photophysics; nanophotonics; Mie resonancesPhysics::Atomic and Molecular Clusters[CHIM]Chemical SciencesGeneral Materials ScienceThin filmPhysics::Chemical PhysicsPerovskite (structure)[PHYS]Physics [physics]Condensed Matter - Materials Sciencebusiness.industryMie resonancesGeneral EngineeringMaterials Science (cond-mat.mtrl-sci)Fano resonanceMetamaterialSettore ING-INF/02 - Campi Elettromagnetici021001 nanoscience & nanotechnology0104 chemical sciencesOptoelectronicsFano resonancenanophotonics0210 nano-technologybusinessultrafast photophysicsUltrashort pulseOptics (physics.optics)Physics - Optics
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