Dissertations / Theses on the topic 'Wigner equation'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 15 dissertations / theses for your research on the topic 'Wigner equation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Mugassabi, Souad. "Schrödinger equation with periodic potentials." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4895.
Full textPhilip, Timothy. "Error analysis of boundary conditions in the Wigner transport equation." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54031.
Full textManfredi, Giovanni. "Sur les modèles de Vlasov, Schrödinger et Wigner en physique des plasmas : redimensionnement et expansion dans le vide." Orléans, 1994. http://www.theses.fr/1994ORLE2027.
Full textWeetman, Philip. "Modelling Quantum Well Lasers." Thesis, University of Waterloo, 2002. http://hdl.handle.net/10012/1262.
Full textChabu, Victor. "Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1029/document.
Full textIn the first part of this thesis we study the propagation of Wigner measures linked to solutions of the Schrödinger equation with potentials presenting conical singularities and show that they are transported by two different Hamiltonian flows, one over the bundle cotangent to the singular set and the other elsewhere in the phase space, up to a transference phenomenon between these two regimes that may arise whenever trajectories in the outsider flow lead in or out the bundle. We describe in detail either the flow and the mass concentration around and on the singular set and illustrate with examples some issues raised by the lack of uniqueness for the classical trajectories on the singularities despite the uniqueness of quantum solutions, dismissing any classical selection principle, but in some cases being able to fully solve the problem.In the second part we present a work in collaboration with Dr. Clotilde Fermanian and Dr. Fabricio Macià where we analyse a Schrödinger-like equation pertinent to the semiclassical study of the dynamics of an electron in a crystal with impurities, showing that in the limit where the characteristic lenght of the crystal's lattice can be considered sufficiently small with respect to the variation of the exterior potential modelling the impurities, then this equation is approximated by an effective mass equation, or, more generally, that its solution decomposes in terms of Bloch modes, each of them satisfying an effective mass equation specificly assigned to their Bloch energies
Kefi, Jihène. "Analyse mathématique et numérique de modèles quantiques pour les semiconducteurs." Toulouse 3, 2003. http://www.theses.fr/2003TOU30186.
Full textMennane, Lahcen. "Méthodes semi-classiques pour la résolution des équations du type Bethe-Goldstone." Grenoble 1, 1990. http://www.theses.fr/1990GRE10079.
Full textColin, Thierry. "Problème de Cauchy et effets régularisants pour des équations aux dérivées partielles dispersives." Cachan, Ecole normale supérieure, 1993. http://www.theses.fr/1993DENS0003.
Full textHurst, Jerome. "Ultrafast spin dynamics in ferromagnetic thin films." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAE004/document.
Full textIn this thesis we focus on the theoritical description and on the numerical simulation of the charge and spin dynamics in metallic nano-structures. The physics of metallic nano-structures has stimulated a huge amount of scientific interest in the last two decades, both for fundamental research and for potential technological applications. The thesis is divided in two parts. In the first part we use a semiclassical phase-space model to study the ultrafast charge and spin dynamics in thin ferromagnetic films (Nickel). Both itinerant and localized magnetism are taken into account. It is shown that an oscillating spin current can be generated in the film via the application of a femtosecond laser pulse in the visible range. In the second part we focus on the charge dynamics of electrons confined in metallic nano-particles (Gold) or anisotropic wells. We show that such systems can be used for high harmonic generation
Rouffort, Clément. "Théorie de champ-moyen et dynamique des systèmes quantiques sur réseau." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S074/document.
Full textThis thesis is dedicated to the mathematical study of the mean-field approximation of Bose gases. In quantum physics such approximation is regarded as the primary approach explaining the collective behavior appearing in large quantum systems and reflecting fundamental phenomena as the Bose-Einstein condensation and superfluidity. In this thesis, the accuracy of the mean-field approximation is proved in full generality as a consequence only of scaling and symmetry principles. Essentially all the known results in the subject are recovered and new ones are proved specifically for quantum lattice systems including the Bose-Hubbard model. On the other hand, our study sets a bridge between the Gross-Pitaevskii and Hartree hierarchies related to the BBGKY method of statistical physics with certain transport or Liouville's equations in infinite dimensional spaces. As an outcome, the uniqueness property for these hierarchies is proved in full generality using only generic features of some related initial value problems. Again, several new well-posedness results as well as a counterexample to uniqueness for the Gross-Pitaevskii hierarchy equation are proved. The originality in our works lies in the use of Liouville's equations and powerful transport techniques extended to infinite dimensional functional spaces together with Wigner probability measures and a second quantization approach. Our contributions can be regarded as the culmination of the ideas initiated by Z. Ammari, F. Nier and Q. Liard in the mean-field theory
El, Hajjj Raymond. "Etude mathématique et numérique de modèles de transport." Toulouse 3, 2008. http://thesesups.ups-tlse.fr/353/.
Full textThis thesis is decomposed into three parts. The main part is devoted to the study of spin polarized currents in semiconductor materials. An hierarchy of microscopic and macroscopic models are derived and analyzed. These models takes into account the spin relaxation and precession mechanisms acting on the spin dynamics in semiconductors. We have essentially two mechanisms : the spin-orbit coupling and the spin-flip interactions. We begin by presenting a semiclassical analysis (via the Wigner transformation) of the Schrödinger equation with spin-orbit hamiltonian. At kinetic level, the spinor Vlasov (or Boltzmann) equation is an equation of distribution function with 2x2 hermitian positive matrix value. Starting then from the spinor form of the Boltzmann equation with different spin-flip and non spin-flip collision operators and using diffusion asymptotic technics, different continuum models are derived. We derive drift-diffusion, SHE and Energy-Transport models of two-components or spin-vector types with spin rotation and relaxation effects. Two numerical applications are then presented : the simulation of transistor with spin rotational effect and the study of spin accumulation effect in inhomogenous semiconductor interfaces. In the second part, the diffusion limit of the linear Boltzmann equation with a strong magnetic field is performed. The Larmor radius is supposed to be much smaller than the mean free path. The limiting equation is shown to be a diffusion equation in the parallel direction while in the orthogonal direction, the guiding center motion is obtained. The diffusion constant in the parallel direction is obtained through the study of a new collision operator obtained by averages of the original one. Moreover, a correction to the guiding center motion is derived. .
GIOVANNINI, ELISA. "A Wigner Equation with Decoherence." Doctoral thesis, 2020. http://hdl.handle.net/2158/1238624.
Full textZAMPONI, NICOLA. "Quantum fluid models for electron transport in graphene." Doctoral thesis, 2013. http://hdl.handle.net/2158/804472.
Full textLasater, Matthew S. "Numerical methods for the Wigner-Poisson equations." 2005. http://www.lib.ncsu.edu/theses/available/etd-10052005-160240/unrestricted/etd.pdf.
Full textDhamo, Elidon [Verfasser]. "Dispersive effects in quantum kinetic equations : the Wigner-Poisson-Fokker-Planck system / Elidon Dhamo." 2006. http://d-nb.info/991233867/34.
Full text