English
Related papers

Related papers: Generalized drift-diffusion model for miniband sup…

200 papers

In this paper, we extend and complement previous works about propagation in kinetic reaction-transport equations. The model we study describes particles moving according to a velocity-jump process, and proliferating according to a reaction…

Analysis of PDEs · Mathematics 2017-07-12 Emeric Bouin , Nils Caillerie

We propose to use spin hydrodynamics, a two-fluid model of spin propagation, as a generalization of the diffusion equation. We show that in the dense limit spin hydrodynamics reduces to Fick's law and the diffusion equation. In the opposite…

Quantum Gases · Physics 2016-11-02 Thomas Schaefer

The peridynamic model of a solid does not involve spatial gradients of the displacement field and is therefore well suited for studying defect propagation. Here, bond-based peridynamic theory is used to study the equilibrium and steady…

Computational Physics · Physics 2018-05-09 Linjuan Wang , Rohan Abeyaratne

We present the detailed analysis of the diffusive transport of spatially inhomogeneous fluid mixtures and the interplay between structural and dynamical properties varying on the atomic scale. The present treatment is based on different…

Mesoscale and Nanoscale Physics · Physics 2011-05-19 Umberto Marini Bettolo Marconi , Simone Melchionna

We develop a drift-diffusion equation that describes electron spin polarization density in two-dimensional electron systems. In our approach, superpositions of spin-up and spin-down states are taken into account, what distinguishes our…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Yuriy V. Pershin

A simplified relativistic kinetic theory for gases with internal degrees of freedom, based on a BGK-type collision term, is considered. First the Boltzmann equation is rewritten in tetrad form and then thermal coefficients are determined to…

General Relativity and Quantum Cosmology · Physics 2026-04-13 Philip Semrén , Michael Bradley , João M. S. Oliveira , M. Piedade Machado Ramos

We present Chapman--Enskog and Hilbert expansions applied to the $\BigO(v/c)$ Boltzmann equation for the radiative transfer of neutrinos in core-collapse supernovae. Based on the Legendre expansion of the scattering kernel for the collision…

Analysis of PDEs · Mathematics 2013-08-07 Heiko Berninger , Emmanuel Frenod , Martin Gander , Mathias Liebendorfer , Jerome Michaud

The Boltzmann kinetic theory for a model of a confined quasi-two dimensional granular mixture derived previously [Garz\'o, Brito and Soto, Phys. Fluids \textbf{33}, 023310 (2021)] is considered further to analyze two different problems.…

Soft Condensed Matter · Physics 2024-03-07 Vicente Garzó , Ricardo Brito , Rodrigo Soto

A paradigm model is suggested for describing the diffusive limit of trajectories of two Lorentz disks moving in a finite horizon periodic configuration of smooth, strictly convex scatterers and interacting with each other via elastic…

Mathematical Physics · Physics 2010-08-06 Zsolt Pajor-Gyulai , Domokos Szász

Consider the initial-boundary value problem for the 2-speed Carleman model of the Boltzmann equation of the kinetic theory of gases set in some bounded interval with boundary conditions prescribing the density of particles entering the…

Analysis of PDEs · Mathematics 2012-07-27 François Golse , Francesco Salvarani

In recent works it has been demonstrated that using an appropriate rescaling, linear Boltzmann-type equations give rise to a scalar fractional diffusion equation in the limit of a small mean free path. The equilibrium distributions are…

Mathematical Physics · Physics 2014-10-01 Sabine Hittmeir , Sara Merino-Aceituno

We present the arising of the Fick cross-diffusion system of equations for fluid mixtures from the multi-species Boltzmann in a rigorous manner in Sobolev spaces. To this end, we formally show that, in a diffusive scaling, the…

Analysis of PDEs · Mathematics 2020-03-19 Marc Briant , Bérénice Grec

The present paper discusses the diffusion approximation of the linear Boltzmann equation in cases where the collision frequency is not uniformly large in the spatial domain. Our results apply for instance to the case of radiative transfer…

Analysis of PDEs · Mathematics 2015-03-23 Claude Bardos , Etienne Bernard , François Golse , Rémi Sentis

Consider the linear Boltzmann equation of radiative transfer in a half-space, with constant scattering coefficient $\sigma$. Assume that, on the boundary of the half-space, the radiation intensity satisfies the Lambert (i.e. diffuse)…

Analysis of PDEs · Mathematics 2018-09-18 Claude Bardos , François Golse , Iván Moyano

We have theoretically investigated two-band models of graded-gap superlattices within the envelope-function approximation. Assuming that the gap varies linearly with spatial coordinate, we are able to find exact solutions of the…

Condensed Matter · Physics 2015-06-25 B. Mendez , F. Dominguez-Adame

This paper models the classical diffusion of a main particle through a heatbath by means of a pre-limit microscopic representation of its drifted momentum and energy transfers at collision times. The collision point linear interpolated path…

Mathematical Physics · Physics 2007-05-23 Johan Beumee

The existence of global weak solutions to a coupled spin drift-diffusion and Maxwell-Landau-Lifshitz system is proved. The equations are considered in a two-dimensional magnetic layer structure and are supplemented with Dirichlet-Neumann…

Analysis of PDEs · Mathematics 2015-08-12 Nicola Zamponi , Ansgar Jüngel

A spatially-periodic longitudinal wave is considered in relativistic dissipative hydrodynamics. At sufficiently small wave amplitudes, an analytic solution is obtained in the linearised limit of the macroscopic conservation equations within…

Fluid Dynamics · Physics 2018-03-07 Victor E. Ambrus

The implementation of the kinetic diffuse boundary condition with the characteristic streaming-collision mechanism is studied for the high-order lattice Boltzmann (LB) models. The obtained formulation is also tested and validated…

Fluid Dynamics · Physics 2012-09-25 Jianping Meng , Yonghao Zhang

Spin transport properties at finite electric and magnetic fields are studied by using the generalized semiclassical Boltzmann equation. It is found that the spin diffusion equation for non-equilibrium spin density and spin currents involves…

Materials Science · Physics 2009-11-07 Y. Qi , S. Zhang