Search results for "Light"
showing 10 items of 3575 documents
Quantum well intermixing in GaInNAs/GaAs structures
2003
We report on the characteristics of quantum well intermixing in GaInNAs/GaAs structures of differing N content. Rapid thermal annealing combined with SiO2 caps deposited on the surface of the samples is used to disorder 1.3 mum GaInNAs/GaAs multiquantum wells which have been preannealed in-situ to the stage of blueshift saturation. The different effects of two capping layer deposition techniques on the interdiffusion of In-Ga have been compared, particular regarding the role of sputtering processes. The dependence of quantum well intermixing-induced photoluminescence blueshift on N concentration has provided extra information on the intrinsic properties of the GaInNAs/GaAs material system. …
Effects of rapid thermal annealing on the optical properties of low-loss 1.3μm GaInNAs∕GaAs saturable Bragg reflectors
2004
We report studies of the effect of rapid thermal annealing (RTA) on the optical properties of a low-loss 1.3 mum saturable Bragg reflector (SBR), consisting of a GaInNAs/GaAs single quantum well embedded in an AlAs/GaAs Bragg reflector grown monolithically on a GaAs substrate. RTA gives rise to a blueshift of the photoluminescence (PL) peak (and therefore of the excitonic absorption peak) and an enhancement of PL intensity, while the reflectivity properties including peak reflectivity and bandwidth are not degraded. Temperature dependent photoluminescence measurements show that the RTA-induced blueshift of photoluminescence consists of two components: one originating from the increase of op…
Erwinia piriflorinigrans sp. nov., a novel pathogen that causes necrosis of pear blossoms
2010
Eight Erwinia strains, isolated from necrotic pear blossoms in València, Spain, were compared with reference strains of Erwinia amylovora and Erwinia pyrifoliae, both of which are pathogenic to species of pear tree, and to other species of the family Enterobacteriaceae using a polyphasic approach. Phenotypic analyses clustered the novel isolates into one phenon, distinct from other species of the genus Erwinia, showing that the novel isolates constituted a homogeneous phenotypic group. Rep-PCR profiles, PCR products obtained with different pairs of primers and plasmid contents determined by restriction analysis showed differences between the novel strains and reference strains of E. amylovo…
Metabolic signatures across the full spectrum of non-alcoholic fatty liver disease.
2022
Funder: European Commission
Search for neutrino emission from gamma-ray flaring blazars with the ANTARES telescope
2012
The ANTARES telescope observes a full hemisphere of the sky all the time with a duty cycle close to 100%. This makes it well suited for an extensive observation of neutrinos produced in astrophysical transient sources. In the surrounding medium of blazars, i.e. active galactic nuclei with their jets pointing almost directly towards the observer, neutrinos may be produced together with gamma-rays by hadronic interactions, so a strong correlation between neutrinos and gamma-rays emissions is expected. The time variability information of the studied source can be obtained by the gamma-ray light curves measured by the LAT instrument on-board the Fermi satellite. If the expected neutrino flux ob…
Fundamentals of 3D imaging and displays: a tutorial on integral imaging, light-field, and plenoptic systems
2018
There has been great interest in researching and implementing effective technologies for the capture, processing, and display of 3D images. This broad interest is evidenced by widespread international research and activities on 3D technologies. There is a large number of journal and conference papers on 3D systems, as well as research and development efforts in government, industry, and academia on this topic for broad applications including entertainment, manufacturing, security and defense, and biomedical applications. Among these technologies, integral imaging is a promising approach for its ability to work with polychromatic scenes and under incoherent or ambient light for scenarios fro…
The large trans-Neptunian object 2002 TC 302 from combined stellar occultation, photometry, and astrometry data
2020
All authors: Ortiz, J. L.; Santos-Sanz, P.; Sicardy, B.; Benedetti-Rossi, G.; Duffard, R.; Morales, N.; Braga-Ribas, F.; Fernández-Valenzuela, E.; Nascimbeni, V.; Nardiello, D.; Carbognani, A.; Buzzi, L.; Aletti, A.; Bacci, P.; Maestripieri, M.; Mazzei, L.; Mikuz, H.; Skvarc, J.; Ciabattari, F.; Lavalade, F. Scarfi, G.; Mari, J. M.; Conjat, M.; Sposetti, S.; Bachini, M.; Succi, G.; Mancini, F.; Alighieri, M.; Dal Canto, E.; Masucci, M.; Vara-Lubiano, M.; Gutiérrez, P. J.; Desmars, J.; Lecacheux, J.; Vieira-Martins, R.; Camargo, J. I. B.; Assafin, M.; Colas, F.; Beisker, W.; Behrend, R.; Mueller, T. G.; Meza, E.; Gomes-Junior, A. R.; Roques, F.; Vachier, F.; Mottola, S.; Hellmich, S.; Campo …
Light-induced transmission nonlinearities in gallium selenide
1999
The intensity of a He–Ne laser (633 nm, 5 mW) transmitted by different GaSe samples is observed to change in correlation with a Nd-yttrium–aluminum–garnet laser pulse (532 nm, 7.8 ns, 3 mJ) which excites them. Such time response has been attributed to a nonlinear optical effect, i.e., a decrease in the refractive index due to the exciton screening by the photogenerated carriers. A calculation of the absorption coefficient and refractive index at different carrier concentrations has led to a reconstruction of transmittance transients which fully agree with the experimental data at different incident intensities and temperatures. Chantal.Ferrer@uv.es ; Jaqueline.Bouvier@uv.es ; Miguel.Andres@…
Ag11(SG)7 : A New Cluster Identified by Mass Spectrometry and Optical Spectroscopy
2014
We report a one-step and high yield synthesis of a red-luminescent silver cluster with the molecular formula, Ag11(SG)7 (SG: glutathionate) via reduction of silver ions by sodium borohydride in the presence of the tripeptide, glutathione (GSH). The as-prepared cluster shows prominent absorption features at 485 and 625 nm in its UV-vis absorption spectrum. Aging of the as-prepared cluster solution led to the disappearance of the 625 nm peak, followed by broadening of the 485 nm peak to give three maxima at ?487, 437, and 393 nm in its absorption spectrum. These peaks remain unchanged even after polyacrylamide gel electrophoresis (PAGE), where a single band was observed confirming high purity…
Children's segment specific light physical activity across two years of school-based program
2015
Making sure that children do not sit down for long periods of time can help them perform better in school and to improve their health. The aim of the study was to examine the patterns of children's light physical activity patterns and gender differences through the Physical Activity as Civil Skill Program 2012-2014. The program was designed to create a new physically active school culture, which required changes in psychological and physical school environment. The sample comprised 76 elementary school children at age of 10 to 13-year-old in Northeast-Finland. The data was collected through three measurement phases from October 2012 to April 2014. Accelerometers were used for the objective …