Search results for "Wave"
showing 10 items of 6009 documents
Vector FWM in optical fibers: tuning techniques and applications
2022
Recientemente, el efecto no lineal de mezcla de cuatro ondas (FWM) en fibras ópticas ha atraído un gran interés para el desarrollo de nuevas fuentes de luz de fibra óptica debido a la emisión de luz múltiple producida por este efecto no lineal. En los últimos años, estas fuentes de luz basadas en FWM han demostrado una gran utilidad en áreas como la óptica cuántica y la microscopía avanzada basada en efecto Raman. Además, según el estado de polarización de la luz de bombeo responsable del efecto FWM y la birrefringencia de la fibra, la luz producida por FWM puede presentar diferentes propiedades de polarización dada la naturaleza vectorial de FWM. Esto posibilita el diseño y desarrollo de f…
First study of the two-body scattering involving charm hadrons
2022
Physical review / D 106(5), 052010 (2022). doi:10.1103/PhysRevD.106.052010
Transformaciones multiescala no lineales
2013
La transformada wavelet y la multirresolución à la Harten son dos herramientas matemáticas que han sido aplicadas con éxito al tratamiento de señales digitales. En los últimos años, este campo ha experimentado un creciente interés debido a sus múltiples aplicaciones como, entre otras, la compresión de imágenes, eliminación de ruido, reconocimiento de patrones, recuperación de fotografías, en campos tan diversos como la Informática, Física, Medicina o Ingeniería. Iniciamos esta tesis con la revisión de estos conceptos. En 1993 A. Harten, [A. Harten. Discrete multiresolution analysis and generalized wavelets. J. Appl. Numer. Math., 12:153–192 (1993)], generaliza un cierto tipo de wavelets bio…
Hydrography and food distribution during a tidal cycle above a cold-water coral mound
2022
Cold-water corals (CWCs) are important ecosystem engineers in the deep sea that provide habitat for numerous species and can form large coral mounds. These mounds influence surrounding currents and induce distinct hy- drodynamic features, such as internal waves and episodic downwelling events that accelerate transport of organic matter towards the mounds, supplying the corals with food. To date, research on organic matter distribution at coral mounds has focussed either on seasonal timescales or has provided single point snapshots. Data on food distribution at the timescale of a diurnal tidal cycle is currently limited. Here, we integrate physical, biogeochemical, and biological data throug…
Synthesis and characterization of chalcogenide glasses from the system Ga-Ge-Sb-S and preparation of a single-mode fiber at 1.55 μm
2008
International audience; The aim of this work is to study different compositions in the Ga-Ge-Sb-S system for the definition of two compositions compatible with the elaboration of a single-mode fiber at the 1.55 μm telecom wavelength. The variations of the glass transition temperature (Tg), the dilatation coefficient (α) and the refractive index (n) have been studied for two glasses series: GaxGe25−xSb10S65 (series 1), Ga5Ge25−xSb10S60+x (series 2). This study has lead to the choice of the Ga4Ge21Sb10S65 composition as clad glass for the preparation of the single-mode fiber and Ga5Ge20Sb10S65 composition as the core. The discrepancies for the studied parameters between the core and clad comp…
Multiple scattering approach for two-electron resonant emission studied by angle-resolved coincidence spectroscopy.
2008
International audience; We have developed a generalization of the multiple-scattering formalism to deal with Auger-photoelectron coincidence spectroscopy APECS in the solid state. We have merged the exact atomic treatment of the angular correlations between the two electrons and the single-particle approach, on which the multiplescattering description of condensed matter relies. This allows the recovering, even in extended systems, of the entangled form of the electron-pair wave function characterizing the coincidence angular diffraction pattern. In the atomic limit our formalism correctly reproduces the cross section, as calculated within the statistical-tensors approach, usually employed …
Monte Carlo simulations of the solid-liquid transition in hard spheres and colloid-polymer mixtures
2010
Monte Carlo simulations at constant pressure are performed to study coexistence and interfacial properties of the liquid-solid transition in hard spheres and in colloid-polymer mixtures. The latter system is described as a one-component Asakura-Oosawa (AO) model where the polymer's degrees of freedom are incorporated via an attractive part in the effective potential for the colloid-colloid interactions. For the considered AO model, the polymer reservoir packing fraction is eta_p^r=0.1 and the colloid-polymer size ratio is q=sigma_p/\sigma=0.15 (with sigma_p and sigma the diameter of polymers and colloids, respectively). Inhomogeneous solid-liquid systems are prepared by placing the solid fc…
On the carrier of inertia
2018
A change in momentum will inevitably perturb the all-embracing vacuum, whose reaction we understand as inertia. Since the vacuum's physical properties relate to light, we propose that the vacuum embodies photons, but in pairs without net electromagnetic fields. In this physical form the free space houses energy in balance with the energy of matter in the whole Universe. Likewise, we reason that a local gravitational potential is the vacuum in a local balance with energy that is bound to a body. Since a body couples to the same vacuum universally and locally, we understand that inertial and gravitational masses are identical. By the same token, we infer that gravity and electromagnetism shar…
Corrosion and wear resistance of coatings produced on AZ31 Mg alloy by plasma electrolytic oxidation in silicate-based K2TiF6 containing solution: Ef…
2022
Abstract In this research, plasma electrolytic oxidation coatings were prepared on AZ31 Mg alloy in a silicate-based solution containing K2TiF6 using bipolar and soft sparking waveforms with 10, 20, and 30% cathodic duty cycles. The coatings displayed a net-like surface morphology consisted of irregular micro-pores, micro-cracks, fused oxide particles, and a sintered structure. Due to the incorporation of TiO2 colloidal particles and the cathodic pulse repair effect, most of the micro-pores were sealed. Long-term corrosion performance of the coatings was investigated using electrochemical impedance spectroscopy during immersion in 3.5 wt.% NaCl solution up to 14 days. The coating grown by t…
Size-consistent ab initio calculation of the electric quadrupole moment of Cl2
2003
Abstract The molecular electric quadrupole moment ( Θ ) of Cl 2 has been calculated using SDCI, and (SC) 2 -SDCI wave functions as well as CCSD, CCSD(T), and CC3 methods. All these correlation methods are single reference. All of them, but SDCI, are free of the size-extensivity error. The variation of Θ from the separated atoms to the equilibrium region is reported. The present results leads to an estimated value of 2.3520 a.u. (10.55 × 10 −40 Cm 2 ) corresponding to a CC(3) calculation at the CBS approach and including the ro-vibrational and thermal averaging corrections. This value is compatible with two experimental values and points to one of them as slightly more reliable.