English
Related papers

Related papers: A fast dynamo on the three-torus

200 papers

This paper aims to numerically verify the large Reynolds number asymptotic theory of magneto-hydrodynamic (MHD) flows proposed in the companion paper Deguchi (2019). To avoid any complexity associated with the chaotic nature of turbulence…

Fluid Dynamics · Physics 2019-09-04 Kengo Deguchi

In this paper, we study the domain wall motion induced by vertical current flow in asymmetric magnetic tunnel junctions. The domain wall motion in the free layer is mainly dictated by the current-induced field-like torque acting on it. We…

Mesoscale and Nanoscale Physics · Physics 2022-02-09 S. Liu , D. J. P. de Sousa , M. Sammon , J. P. Wang , Tony Low

We develop a systematic asymptotic description for domain wall motion in one-dimensional magnetic nanowires under the influence of small applied magnetic fields and currents and small material anisotropy. The magnetization dynamics, as…

Materials Science · Physics 2013-10-17 Arseni Goussev , Ross G. Lund , JM Robbins , Valeriy Slastikov , Charles Sonnenberg

Based on the new findings on the turbulent dynamo in \citet{XL16}, we examine the magnetic field amplification in the context of supernova remnants. Due to the strong ion-neutral collisional damping in the weakly-ionized interstellar…

High Energy Astrophysical Phenomena · Physics 2017-12-13 Siyao Xu , Alex Lazarian

We review some of the recent progress on modeling planetary and stellar dynamos. Particular attention is given to the dynamo mechanisms and the resulting properties of the field. We present direct numerical simulations using a simple…

Solar and Stellar Astrophysics · Physics 2015-06-12 Emmanuel Dormy , Ludovic Petitdemange , Martin Schrinner

Several lines of evidence suggest that protogalactic and galactic environments manage to grow magnetic field very rapidly. This makes the theoretical problem of achieving rapid growth of magnetic fields in such environments difficult.…

Astrophysics · Physics 2009-11-10 D. S. Balsara , J. S. Kim , M. M. Mac Low , G. Mathews

Using a Ginzburg-Landau model, we study the vortex behavior of a rectangular thin film superconductor subjected to an applied current fed into a portion of the sides and an applied magnetic field directed orthogonal to the film. Through a…

Analysis of PDEs · Mathematics 2015-06-12 Lydia Peres Hari , Jacob Rubinstein , Peter Sternberg

In this paper, we study the asymptotic behaviors of solutions to the inhomogeneous Navier-Stokes-Vlasov system in $\mathbb{R}^{3}\times\mathbb{R}^{3}$, where the initial fluid density is allowed to vanish. We establish the uniform bound of…

Analysis of PDEs · Mathematics 2025-05-12 Hai-Liang Li , Ling-Yun Shou , Yue Zhang

Motivated by the difference between the dynamics of magnetization textures in ferromagnets and antiferromagnets, the Landau-Lifshitz equation of motion is explored. A typical one-dimensional domain wall in a bulk ferromagnet with biaxial…

Materials Science · Physics 2020-03-25 Ricardo Rama-Eiroa , Rubén M. Otxoa , Pierre E. Roy , Konstantin Y. Guslienko

The spatiotemporal structure formation problem is investigated in the region far above the transverse ferromagnetic resonance instability. The investigations are based on the dissipative Landau-Lifshitz equation and have been performed on a…

Pattern Formation and Solitons · Physics 2007-05-23 K. Mayes , T. Plefka , H. Sauermann

We present an effectively global analytical asymptotic galactic dynamo solution for the regular magnetic field of an axisymmetric thin disc in the saturated state. This solution is constructed by combining two well-known types of local…

Astrophysics of Galaxies · Physics 2016-09-02 Luke Chamandy

We study a new type of large-scale instability, which arises in obliquely rotating stratified electroconductive fluid with an external uniform magnetic field and a small-scale external force having zero helicity. This force gives rise to…

Fluid Dynamics · Physics 2018-07-06 M. I. Kopp , K. N. Kulik , A. V. Tur , V. V. Yanovsky

The dynamo mechanism is a process of magnetic field self-excitation in a moving electrically conducting fluid. One of the most interesting applications of this mechanism related to the astrophysical systems is the case of a random motion of…

Solar and Stellar Astrophysics · Physics 2021-08-04 E. A. Illarionov , D. D. Sokoloff

The paper develops and studies a very general notion of dichotomy, referred to as "nonuniform $(h,k,\mu,\nu)$-dichotomy". The new notion contains as special cases most versions of dichotomy existing in the literature. The paper then…

Dynamical Systems · Mathematics 2015-04-21 Jimin Zhang , Meng Fan , Liu Yang

We study large-scale dynamo action due to turbulence in the presence of a linear shear flow. Our treatment is quasilinear and equivalent to the standard `first order smoothing approximation'. However it is non perturbative in the shear…

Astrophysics of Galaxies · Physics 2010-02-16 S. Sridhar , Kandaswamy Subramanian

We address the dynamics of magnetic domain walls in ferromagnetic nanowires under the influence of external time-dependent magnetic fields. We report a new exact spatiotemporal solution of the Landau-Lifshitz-Gilbert equation for the case…

Materials Science · Physics 2010-04-13 Arseni Goussev , JM Robbins , Valeriy Slastikov

We investigate numerically the self-sustained dynamo action in a spinning sphere whose sense of rotation reverses periodically. This system serves as a simple model of a dynamo in small bodies powered by frequent collisions. It is found…

Geophysics · Physics 2015-06-18 Xing Wei , Rainer Arlt , Andreas Tilgner

In this paper, we study stability properties of nonuniform hyperbolicity for evolution processes associated with differential equations in Banach spaces. We prove a robustness result of nonuniform hyperbolicity for linear evolution…

Invariant manifolds are fundamental tools for describing and understanding nonlinear dynamics. In this paper, we present a theory of stable and unstable manifolds for infinite dimensional random dynamical systems generated by a class of…

Dynamical Systems · Mathematics 2019-08-15 Jinqiao Duan , Kening Lu , Bjorn Schmalfuss

Geometrical tools, used in Einstein's general relativity (GR), are applied to dynamo theory, in order to obtain fast dynamo action bounds to magnetic energy, from Killing symmetries in Ricci flows. Magnetic field is shown to be the shear…

Mathematical Physics · Physics 2009-05-12 Garcia de Andrade