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Related papers: How Alfven's theorem explains the Meissner effect

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It is generally believed that superconducting materials are divided into two classes: `conventional' and `unconventional'. Conventional superconductors (the elements and thousands of compounds including $MgB_2$) are described by…

Superconductivity · Physics 2012-02-09 J. E. Hirsch

A theorem on the magnetic energy minimum in a perfect, or ideal, conductor is proved. Contrary to conventional wisdom the theorem provides a classical explanation of the expulsion of a magnetic field from the interior of a conductor that…

Superconductivity · Physics 2009-12-09 Miguel C. N. Fiolhais , Hanno Essen , C. Providencia

From the outset of superconductivity research it was assumed that no electrostatic fields could exist inside superconductors, and this assumption was incorporated into conventional London electrodynamics. Yet the London brothers themselves…

Superconductivity · Physics 2012-07-06 J. E. Hirsch

Superfluidity and superconductivity have many elements in common. However, I argue that their most important commonality has been overlooked: that both are kinetic energy driven. Clear evidence that superfluidity in $^4He$ is kinetic energy…

Superconductivity · Physics 2013-09-05 J. E. Hirsch

We propose a dynamical explanation of the Meissner effect in superconductors and predict the existence of a spin Meissner effect: that a macroscopic spin current flows within a London penetration depth $\lambda_L$ of the surface of…

Superconductivity · Physics 2008-03-02 J. E. Hirsch

It was recently pointed out that so-called "superhydrides", hydrogen-rich materials that appear to become superconducting at high temperatures and pressures, exhibit physical properties that are different from both conventional and…

Superconductivity · Physics 2021-06-24 J. E. Hirsch , F. Marsiglio

We review the literature on what classical physics has to say about the Meissner effect and the London equations. We first discuss the relevance of the Bohr-van Leeuwen theorem for the perfect diamagnetism of superconductors. The conclusion…

Classical Physics · Physics 2012-01-26 Hanno Essen , Miguel C. N. Fiolhais

The boundary effects in the screening of an applied magnetic field in a charged anyon fluid at finite temperature and density are investigated. By analytically solving the extremum equations of the sytem and minimizing the free energy…

High Energy Physics - Theory · Physics 2007-05-23 E. J. Ferrer , V. de la Incera

The Meissner effect for superconductors in spacetimes with torsion is revisited. Two new physical interpretations are presented. The first considers the Landau-Ginzburg theory yields a new symmetry-breaking vacuum depending on torsion. In…

Condensed Matter · Physics 2016-08-31 L. C. Garcia de Andrade

When a magnetic field is turned on, a superconducting body acquires an angular momentum in direction opposite to the applied field. This gyromagnetic effect has been established experimentally and is understood theoretically. However, the…

Superconductivity · Physics 2007-09-11 J. E. Hirsch

The magnetic flux freezing theorem or Alfv\'en's theorem, is a basic principle of ideal magnetohydrodynamics (MHD), a commonly used approximation to describe the aspects of astrophysical and laboratory plasmas. The theorem states that the…

Plasma Physics · Physics 2015-06-12 Eric G. Blackman

The discovery of the Meissner effect was a turning point in the history of superconductivity. It demonstrated that superconductivity is an equilibrium state of matter, thus allowing to use thermodynamics for its study. This provided a…

Superconductivity · Physics 2021-09-27 Vladimir Kozhevnikov

The structure of the Meissner effect in a current-carrying cylindrical wire with arbitrary disorder is studied using a numerical procedure that is exact within the semiclassical approximation. A distribution of currents is found that is…

Superconductivity · Physics 2009-10-31 J. Sánchez-Cañizares , J. Ferrer , F. Sols

As shown in former papers, the nonadiabatic Heisenberg model presents a novel mechanism of Cooper pair formation which is not the result of an attractive electron-electron interaction but can be described in terms of quantum mechanical…

Superconductivity · Physics 2017-06-29 Ekkehard Krüger

In a magnetic field, superconductivity is manifested by total magnetic field expulsion (Meissner effect) or by the penetration of integer multiples of the flux quantum {\Phi}_0. Here we present experimental results revealing magnetic…

We consider force-free plasma waves launched by the motion of conducting material through a magnetic field. We develop a spacetime-covariant formalism for perturbations of a uniform magnetic field and show how the transverse motion of a…

General Relativity and Quantum Cosmology · Physics 2016-06-29 Samuel E. Gralla , Peter Zimmerman

We construct examples of smooth periodic solutions to the Magnetohydrodynamic equations in dimension 2 with positive resistivity for which the topology of the magnetic lines changes under the flow. By Alfv\'en's theorem this is known to be…

Analysis of PDEs · Mathematics 2024-10-10 Gennaro Ciampa

We report on the realization and characterization of a magnetic microtrap for ultra cold atoms near a straight superconducting Nb wire with circular cross section. The trapped atoms are used to probe the magnetic field outside the…

Atomic Physics · Physics 2009-11-13 D. Cano , B. Kasch , H. Hattermann , R. Kleiner , C. Zimmermann , D. Koelle , J. Fortágh

Is superconductivity associated with a lowering or an increase of the kinetic energy of the charge carriers? Conventional BCS theory predicts that the kinetic energy of carriers increases in the transition from the normal to the…

Superconductivity · Physics 2011-05-18 J. E. Hirsch

A superconductor in a magnetic field has surface currents that prevent the magnetic field from penetrating its interior. These currents carry kinetic energy and mechanical momentum. When the temperature is raised and the system becomes…

Superconductivity · Physics 2016-06-28 J. E. Hirsch