Search results for "Optoelectronics"
showing 10 items of 2306 documents
4,4'-[Thiophene-2,5-diylbis(ethyne-2,1-diyl)]dibenzonitrile
2008
In the solid state, the title compound, C(22)H(10)N(2)S, forms centrosymmetric dimers by pairs of non-classical C-H⋯S hydrogen bonds linking approximately coplanar mol-ecules. The benzene ring involved in this inter-action makes a dihedral angle of only 7.21 (16)° with the thio-phene ring, while the other benzene ring is twisted somewhat out of the plane, with a dihedral angle of 39.58 (9)°. The hydrogen-bonded dimers stack on top of each other with an inter-planar spacing of 3.44 Å. C-H⋯N hydrogen bonds link together stacks that run in approximately perpendicular directions. Each mol-ecule thus inter-acts with 12 adjacent mol-ecules, five of them approaching closer than the sum of the van …
Aiming strategy affects performance-related factors in biathlon standing shooting
2021
This study focused on investigating differences in shooting performance and performance related factors between two different aiming strategies (HOLD, low radial velocity during the approach 0.4‐0.2 seconds before triggering, and TIMING, high radial velocity) in biathlon standing shooting. 23 biathletes fired 8x5 standing shots at rest (REST) and 2x5 shots during a race simulation (RACE). Shooting performance (hit point distance from the center of the target), aiming point trajectory and postural balance were measured from each shot. Shooting performance was similar both at REST (HOLD 33±5 mm vs TIMING 38±8 mm, p=0.111) and in RACE (40±11 mm vs 47±12 mm, p=0.194). Better shooting performanc…
Amperometric Biosensor and Front-End Electronics for Remote Glucose Monitoring by Crosslinked PEDOT-Glucose Oxidase
2018
Focusing on the interplay between interface chemistry, electrochemistry, and integrated electronics, we show a novel low-cost and flexible biosensing platform for continuous glucose monitoring. The amperometric biosensing system features a planar three-electrode structure on a plastic substrate, and a wireless near-field communication-powered electronic system performing sensor analog front-end, A/D conversion, digital control, and display tasks. The working electrode is made of electropolymerized poly (3,4-ethylenedioxythiophene) film onto a polyethylene terephthalate/gold electrode followed by immobilization of cross-linked glucose oxidase by glutaraldehyde. The advantages offered by such…
Measurements of Low-Energy Protons using a Silicon Detector for Application to SEE Testing
2021
A silicon detector with a fast electronics chain is used for the dosimetry of protons in the range 0.5-5 MeV at the Centro Nacional de Aceleradores (CNA) 3 MV Tandem laboratory in Seville, Spain. In this configuration, measurements can be performed in pulsed mode, using a digitizer to record event-by-event proton energy depositions. The distributions of deposited energy were obtained thanks to a calibration with an alpha source. Measurements of flux and deposited energy are used to enable single event effect (SEE) testing on selected static random access memories (SRAMs).
Ultrafast Interface Charge Separation in Carbon Nanodot-Nanotube Hybrids
2021
Carbon dots are an emerging family of zero-dimensional nanocarbons behaving as tunable light harvesters and photoactivated charge donors. Coupling them to carbon nanotubes, which are well-known electron acceptors with excellent charge transport capabilities, is very promising for several applications. Here, we first devised a route to achieve the stable electrostatic binding of carbon dots to multi- or single-walled carbon nanotubes, as confirmed by several experimental observations. The photoluminescence of carbon dots is strongly quenched when they contact either semiconductive or conductive nanotubes, indicating a strong electronic coupling to both. Theoretical simulations predict a favo…
High Bias Voltage CZT Detectors for High-flux Measurements
2017
In this work, we present the performance of new travelling heater method (THM) grown CZT detectors, recently developed at IMEM-CNR Parma, Italy. Thick planar detectors (3 mm thick) with gold electroless contacts on CZT crystals grown by Redlen Technologies (Victoria BC, Canada) were realized, with a planar cathode covering the detector surface (4.1 x 4.1 mm(2)) and a central anode (2 x 2 mm(2)) surrounded by a guard ring electrode. The detectors, characterized by low leakage currents at room temperature (4.7 nA/cm(2) at 1000 V/cm), allow good room temperature operation even at high bias voltages (> 7000 V/cm). At low rates, the detectors exhibit an energy resolution around 4 % FWIEM at 59.5…
Charge Transport Mechanisms in Heavy-Ion Driven Leakage Current in Silicon Carbide Schottky Power Diodes
2016
Under heavy-ion exposure at sufficiently high reverse bias voltages silicon carbide (SiC) Schottky diodes are observed to exhibit gradual increases in leakage current with increasing ion fluence. Heavy-ion exposure alters the overall reverse current-voltage characteristics of these diodes, leaving the forward characteristics practically unchanged. This paper discusses the charge transport mechanisms in the heavy-ion damaged SiC Schottky diodes. A macro model, describing the reverse current-voltage characteristics in the degraded SiC Schottky diodes is proposed. peerReviewed
Effect of the Si doping on the properties of AZO/SiC/Si heterojunctions grown by low temperature pulsed laser deposition
2020
Abstract The structural and photoelectrical properties of Al-doped ZnO (AZO)/SiC/p-Si and AZO/SiC/n-Si heterojunctions, fabricated at low temperature by pulsed laser deposition, were investigated by means of a number of techniques. Raman analysis indicates that SiC layers have the cubic 3C-SiC phase, whilst X-ray diffraction measurements show that AZO films exhibit a hexagonal wurtzite structure, highly textured along the c-axis, with average crystallites size of 35.1 nm and lattice parameter c of 0.518 nm. The homogeneous and dense surface morphology observed by scanning electron microscopy was confirmed by atomic force microscopy images. Moreover, UV–Vis-NIR spectra indicated a high trans…
Time resolved emission at 1.3 μm of a single InAs quantum dot by using a tunable fibre Bragg grating
2013
Photoluminescence and time resolved photoluminescence from single metamorphic InAs/GaAs quantum dots (QDs) emitting at 1.3 mu m have been measured by means of a novel fibre-based characterization set-up. We demonstrate that the use of a wavelength tunable fibre Bragg grating filter increases the light collection efficiency by more than one order of magnitude as compared to a conventional grating monochromator. We identified single charged exciton and neutral biexciton transitions in the framework of a random population model. The QD recombination dynamics under pulsed excitation can be understood under the weak quantum confinement potential limit and the interaction between carriers at the …
Characterization of a CZT focal plane small prototype for hard X-ray telescope
2005
The promise of good energy and spatial resolution coupled with high efficiency and room temperature operation has fuelled a large international effort to develop cadmium zinc telluride (CZT) for hard X-ray applications. We are involved on the development of a hard X-ray telescope based on multilayer optics and focal plane detector operative in the 10-80 keV energy range. This telescope requires a high efficiency focal plane providing both fine spatial resolution and spectroscopy with a compact and robust design. This paper reports preliminary results on the characterization both in spectroscopic and spatial response of two small pixellated CZT detectors (10times10times1 mm3 and 10times10tim…