Search results for "Modes"
showing 10 items of 235 documents
Generation of soliton molecules, power regulation, regeneration and sculpting of pulse profiles within a multifunction fiber laser
2018
The work of this thesis strives to provide a solution to the persistent problem of poverty of mode-locked fiber lasers, in terms of functionality and flexibility. The thesis proposes a fiber-laser cavity having the specificity of being multifunctional. The cavity is equipped with tunable components, which provide the flexibility to realize functions ranging from the generation of pulses with complex profiles (solitons, bi-solitons, tri-solitons, etc.) up to the carving of pulse profiles, passing through the regulation of peak powers, and the regeneration of severely degraded intensity profiles. The laser cavity that we propose has the specificity of being controlled by a key component, whic…
Fluctuations and elastic properties of lipid membranes in the gel Lβ′ state: a coarse-grained Monte Carlo study
2010
We study the stress distribution profiles and the height and thickness fluctuations of lipid membranes in the gel L-beta ' state by Monte Carlo simulations of a generic coarse-grained model for lipid membranes, which reproduces many known properties of dipalmitoylphosphatidyncholine (DPPC) bilayers. The results are related to the corresponding properties of fluid membranes, and to theoretical predictions for crystalline and hexatic membranes. One striking observation is that the spontaneous curvature of the monolayers changes sign from the fluid to the gel phase. In the gel-phase, the long-wavelength height fluctuations are suppressed, and the fluctuation spectrum is highly anisotropic. In …
Iterative approximation to a coincidence point of two mappings
2015
In this article two methods for approximating the coincidence point of two mappings are studied and moreover, rates of convergence for both methods are given. These results are illustrated by several examples, in particular we apply such results to study the convergence and their rate of convergence of these methods to the solution of a nonlinear integral equation and of a nonlinear differential equation.
The Peculiar Physical Properties of Nanosized Ferroics (Nanoferroics)
2013
This Chapter contains the experimental facts about size effects in nanoferroics. They include ferroelectric, ferroelastic, magnetic and multiferroic nanostructured materials. The main peculiar feature of nanoferroics is the geometric confinement originating from their surfaces and interfaces. This is in contrast to the ordinary bulk ferroics, where the sample surface plays a minor role. In particular, in nanoferroics, the surface generates the physical properties gradients in the normal (to the surface) direction. This fact yields strong size effects and spatial inhomogeneity of the nanoferroics properties, which should be taken into account to get their adequate physical description. We re…
Experimental evidence for a local disorder in pure and doped perovskites
1992
Abstract In the soft mode picture, the ferroelectric phase transitions in most of ABO3 perovskites are triggered by the long wavelength oscillations of the B ions against their oxygen cage. There is now a lot of experimental evidence that this picture is incomplete. An extra contribution has to be included in the dynamical response. This contribution is usually thought to arise from local lattice distorsions; this is what will be called local disorder. A complete understanding of this local disorder requires the experimental determination of the microscopic origin, of the dynamics and spatial extension of the lattice distorsions. A useful way to summarize these requirements is to use the co…
Three-mode two-boson Jaynes–Cummings model in trapped ions
2006
In this paper, we analyse a two-boson three-mode Jaynes–Cummings model which can be implemented in the context of trapped ions. The symmetries of the Hamiltonian are brought to light and analysed in detail in order to solve the eigenvalue problem. The calculation of the time evolution operator shows the possibility of realizing interesting applications, such as the generation of nonclassical states.
Raman scattering study of the anharmonic effects in CeO2−ynanocrystals
2007
We have studied the temperature dependence of the F2g Raman mode phonon frequency and broadening in CeO2−y nanocrystals. The phonon softening and phonon linewidth are calculated using a model which takes into account the three-and four-phonon anharmonic processes. A detailed comparison of the experimental data with theoretical calculations revealed the predominance of four-phonon anharmonic processes in the temperature dependence of the phonon energy and broadening of the nanocrystals. On the other hand, three-phonon processes dominate the temperature behavior of phonons in polycrystalline samples. The anti-Stokes/Stokes peak intensity ratio was also investigated and found to be smaller for…
Plasmon de surface de particules métalliques toroïdales
2006
This thesis deals with the optical properties of small metal torii. A method of resolution of the equation of Laplace in toroidal coordinates is introduced and the radiative properties of the metal toric nanoparticules are studied within the electrostatic framework. The study on the eigenmodes spatial distribution suggests that metal nanotorus can carry a non-zero magnetic dipole moment at optical frequencies. Analytical expressions for the extinction and scattering cross sections of the torus are also found and compared with numerical simulations and experimental results obtained with collaborations. The sensitivity of the plasmon frequency to the refraction index of the external medium an…
Multimodal approach to foster the Multiliteracies pedagogy in the teaching of EFL through picturebooks: The Snow Lion
2020
espanolEnsenar lenguas en el siglo veintiuno implica prestar atencion a las demandas pedagogicas multimodales de un mundo digital global. Para alcanzar este objetivo, la ensenanza efectiva del ingles requiere una preparacion de los instructores para guiar de manera consciente el desarrollo de la literacidad de los alumnos e integrar las distintas maneras de construir significado que van mucho mas alla del mero uso de la lengua. Este articulo suscribe la nocion de literacidad como un concepto multidimensional y propone un conjunto de herramientas multimodales como medio para que los maestros de ingles como lengua extranjera (ILE) trabajen con elementos literarios y visuales clave. Centrandon…
“I look with deep gratitude and admiration ...” – praising and complimenting in papal speeches
2022
Abstract Recently, communicating admiration and appreciation in public discourse has become a subject of study since these acts play a very important role in shaping positive social relations not only on a micro scale, but also on a macro one. My goal in this study is to understand how public officials implement their intention to please addressees in an international arena, in contacts between different religious and national communities. In order to do this, 120 papal speeches delivered to representatives of different churches, religions and societies were analysed, identifying individual topics, functions and patterns of these speech acts, as well as their dependence on such parameters a…