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Related papers: Intermittency in spherical Couette dynamos

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We construct a smooth velocity field $u$ on $\mathbb{R}_+ \times \mathbb{T}^3$ that exhibits kinematic dynamo action, causing exponential growth in solutions to the magnetohydrodynamic induction equation, with a rate that is uniform in…

Analysis of PDEs · Mathematics 2025-06-02 Keefer Rowan

Several recent advances in turbulent dynamo theory are reviewed. High resolution simulations of small-scale and large-scale dynamo action in periodic domains are compared with each other and contrasted with similar results at low magnetic…

Solar and Stellar Astrophysics · Physics 2012-07-10 Axel Brandenburg , Dmitry Sokoloff , Kandaswamy Subramanian

Magnetic fields of planets, stars and galaxies are generated by self-excitation in moving electrically conducting fluids. Once produced, magnetic fields can play an active role in cosmic structure formation by destabilizing rotational flows…

Fluid Dynamics · Physics 2018-03-12 F. Stefani , A. Gailitis , G. Gerbeth , A. Giesecke. Th. Gundrum , G. Ruediger , M. Seilmayer , T. Vogt

The theory for the quantum tunneling of nano-magnets is developed within the intermediate spin framework. Periodic magnetic effects are seen to reflect that associated with a change of flux by a single flux quantum $\Phi_{0}$. Essential are…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. E. Barnes

In systems where the standard $\alpha$ effect is inoperative, one often explains the existence of mean magnetic fields by invoking the `incoherent $\alpha$ effect', which appeals to fluctuations of the mean kinetic helicity at a mesoscale.…

Solar and Stellar Astrophysics · Physics 2023-10-24 Kishore Gopalakrishnan , Nishant Singh

In the present paper, we theoretically study the effect of density of state variation on the phenomena in the discontinuous magnetic field. Special attention is paid to the transient processes when the magnetic field is switched on (off).…

Mesoscale and Nanoscale Physics · Physics 2019-11-21 Petro Romanets

The fermionic condensate is investigated in a (2+1)-dimensional conical spacetime in the presence of a circular boundary and a magnetic flux. It is assumed that on the boundary the fermionic field obeys the MIT bag boundary condition. For…

High Energy Physics - Theory · Physics 2011-04-22 S. Bellucci , E. R. Bezerra de Mello , A. A. Saharian

Magnetic friction is a form of non-contact friction arising from the dissipation of energy in a magnet due to spin reorientation in a magnetic field. In this paper we study magnetic friction in the context of micromagnetics, using our…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 Ilari Rissanen , Lasse Laurson

We study an example of instability in presence of a multiplicative noise, namely the spontaneous generation of a magnetic field in a turbulent medium. This so-called turbulent dynamo problem remains challenging, experimentally and…

Astrophysics · Physics 2016-08-16 Nicolas Leprovost , Bérengère Dubrulle

Recently, Silvers, Vasil, Brummell, & Proctor (2009), using numerical simulations, confirmed the existence of a double diffusive magnetic buoyancy instability of a layer of horizontal magnetic field produced by the interaction of a shear…

Solar and Stellar Astrophysics · Physics 2015-05-30 Lara J. Silvers , Geoffrey M. Vasil , Nicholas H. Brummell , Michael R. E. Proctor

Turbulence is a complex physical process prevalent in modern physics, particularly in ionized environments like interstellar gas, where magnetic fields play a dynamic role. However, the precise influence of magnetic fields in such settings…

Astrophysics of Galaxies · Physics 2025-08-12 Guang-Xing Li , Mengke Zhao

We consider the classical problem of kinematic dynamo action in simple steady flows. Due to the adjointness of the induction operator, we show that the growth rate of the dynamo will be exactly the same for two types of magnetic boundary…

Fluid Dynamics · Physics 2013-09-25 B. Favier , M. R. E. Proctor

Large-scale magnetic fields in stars and galaxies are thought to arise by mean-field dynamo action due to the combined influence of both helical turbulence and shear. Those systems are also highly conducting and the turbulence therein leads…

Astrophysics of Galaxies · Physics 2019-05-22 Pallavi Bhat , Kandaswamy Subramanian , Axel Brandenburg

In this work we investigate the quench dynamics in the Kondo model on the Toulouse line in presence of a local magnetic field. It is shown that this setup can be realized by either applying the local magnetic field directly or by preparing…

Strongly Correlated Electrons · Physics 2010-09-13 Markus Heyl , Stefan Kehrein

Energy input by under-field rotation of particles drives the systems to emergent non-equilibrium states. Here we investigate the suspension of rotating magnetic cubes. Micron-sized hematite cubes are synthesized and observed…

We investigate the persistent current influenced by the spin fluctuations in a mesoscopic ring weakly coupled to a quantum dot. It is shown that the Kondo effect gives rise to some unusual features of the persistent current in the limit…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Sam Young Cho , Kicheon Kang , Chul Koo Kim , Chang-Mo Ryu

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

We present a high-order numerical study of the dependence of the dynamo onset on different electromagnetic boundary conditions, in convecting Boussinesq flows forced by a temperature gradient. Perfectly conducting boundaries, vacuum, and…

Fluid Dynamics · Physics 2023-03-21 Mauro Fontana , Pablo D. Mininni , Pablo Dmitruk

We present direct numerical simulations of dynamo action in a forced Roberts flow. The behavior of the dynamo is followed as the mechanical Reynolds number is increased, starting from the laminar case until a turbulent regime is reached.…

Fluid Dynamics · Physics 2015-06-26 P. D. Mininni , D. C. Montgomery

Dynamos wherein magnetic field is produced from velocity fluctuations are fundamental to our understanding of several astrophysical and/or laboratory phenomena. Though fluid helicity is known to play a key role in the onset of dynamo…

Plasma Physics · Physics 2023-07-05 Shishir Biswas , Rajaraman Ganesh