Search results for "campi elettromagnetici"
showing 10 items of 155 documents
Universal N-partite d-level pure-state entanglement witness based on realistic measurement settings
2018
Entanglement witnesses are operators that are crucial for confirming the generation of specific quantum systems, such as multipartite and high-dimensional states. For this reason, many witnesses have been theoretically derived which commonly focus on establishing tight bounds and exhibit mathematical compactness as well as symmetry properties similar to that of the quantum state. However, for increasingly complex quantum systems, established witnesses have lacked experimental achievability, as it has become progressively more challenging to design the corresponding experiments. Here, we present a universal approach to derive entanglement witnesses that are capable of detecting the presence …
Opals infiltrated with a stimuli-responsive hydrogel for ethanol vapor sensing
2013
We report on a novel class of optical materials for ethanol vapor sensing, based on polystyrene opals infiltrated with an innovative stimuli responsive hydrogel. We describe the fabrication process of the bare polystyrene opals and their subsequent infiltration. The optical characterization of the photonic crystal templates was performed to prove the good quality of the samples. Measurements on the infiltrated opals showed that the transmission spectra in the visible range strongly change at varying concentrations of ethanol vapor. The fabricated structures show a linear optical response in the visible range, for high values of ethanol concentration.
Fabrication of Graphene Field Effect Transistors (GFET) possessing a photoelectrical response
2014
Harmonic generation in all-dielectric metasurfaces
2023
Nonlinear light generation is a key phenomenon in many optical systems. Recently, the field of nonlinear optics has moved to the miniaturization of conventional bulky components. Among all the new platforms that have been proposed, dielectric nanoscale resonators represent excellent candidates for light generation and manipulation. When arranged in periodic arrays, such high refractive index scattering components become an artificial material called metasurface. Several approaches for designing platforms with enhanced optical nonlinearities at moderate pump intensities have been proposed. In this chapter, we review the most recent results on second- and third-order nonlinear processes in hi…
Homodyne Solid-State Biased Coherent Detection of Ultra-Broadband Terahertz Pulses with Static Electric Fields.
2021
We present an innovative implementation of the solid-state-biased coherent detection (SSBCD) technique, which we have recently introduced for the reconstruction of both amplitude and phase of ultra-broadband terahertz pulses. In our previous works, the SSBCD method has been operated via a heterodyne scheme, which involves demanding square-wave voltage amplifiers, phase-locked to the THz pulse train, as well as an electronic circuit for the demodulation of the readout signal. Here, we demonstrate that the SSBCD technique can be operated via a very simple homodyne scheme, exploiting plain static bias voltages. We show that the homodyne SSBCD signal turns into a bipolar transient when the stat…
New Cost Effective Titanium Based Protective and Decorative Coatings by Ion Plating Plasma Assisted IPPA
2009
The activity aiming to replace galvanic treatments by vacuum processes is based on the effort to reduce the production costs and to set-up new decorative effects impossible to be galvanically realised because the use of dielectric materials. This work describes cost effective metal-oxide and oxide-metal-oxide decorative coatings based on the use of titanium as basic material deposited by Ion Plating Plasma Assisted from Reactive Magnetron Sputtering source. A new multilayer protective and decorative structure, based on the use of titanium and titanium oxides is also presented. The protective effect against aggressive environment is obtained by alternating layers of metal and metal-oxide mix…
Fabrication and electro-optical characterization of Ruthenium-based Dye-Sensitized Solar Cells
2015
In this paper, we measure the main photoelectrical parameters of Dye Sensitized Solar Cells (DSSCs) based on ruthenium complexes at different irradiance levels, incident wavelengths, temperatures and hours of light soaking
Experimental characterization of Ruthenium-based Dye Sensitized Solar Cells and study of light-soaking effect impact on performance
2016
In this paper, we present an experimental investigation on the performance of Ruthenium-based Dye Sensitized Solar Cells (DSSCs) at different irradiance levels, incident wavelengths and hours of illumination. In particular, the measurements have been aimed at studying the performance variation due to light soaking effect since this phenomenon has noteworthy practical implications, such as stability tests of DSSCs. Our results show that the short circuit current density, the open circuit voltage and the conversion efficiency η increase with the hours of light soaking. Finally, the observed phenomenon is reversible, and thus the performance decreases again when the cell is kept in the dark.
Characterization of thin film CIG(S,SE)2 submodules using solar simulator and laser beam induced current techniques (Versione estesa)
2015
In this work, the electrical and optical characterization of CIG(S, Se)2 sub-modules using both a solar simulator equipment and the Laser Beam Induced Current (LBIC) technique is presented. By using the solar simulator and a proper set-up, the electrical parameters of the modules at varying irradiance and temperatures are determined. In addition, the LBIC measurements are carried out to analyze the 2D photocurrent uniformity of the modules at two different wavelengths. Dispersion values of extracted parameters can be very useful for practically tuning the modelling stage at device/module level.
Characterization of Thin Film CIG(S,Se)2 submodules using Laser Beam Induced Current Technique
2015
Nowadays, an important class of thin film solar cells consists of CuInGa(S,Se)2 (CIGSSe) solar cells, i.e., composed of Copper, Indium, Gallium, Sulfur and Selenide. Thanks to their electrical and optical properties and to the technological development, thin film integrated photovoltaic modules have nowadays obtained relatively good values of efficiency. In this work, we have performed the electrical and optical characterization of a CIGSSe sub-module by using both a solar simulator equipment and the Laser Beam Induced Current (LBIC) technique.