相关论文: Meissner Effect and Constraints
Alfven's theorem states that in a perfectly conducting fluid magnetic field lines move with the fluid without dissipation. When a metal becomes superconducting in the presence of a magnetic field, magnetic field lines move from the interior…
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…
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…
I argue that the conventional BCS-London theory of superconductivity does not explain the most fundamental property of superconductors, the Meissner effect: how is the Meissner current generated, and how is it able to defy Faraday's law?…
In this work a periodic crystal with point defects is described in the framework of linear response theory for broken symmetry states using correlation functions and Zwanzig-Mori equations. The main results are microscopic expressions for…
Among the most significant macroscopic quantum phenomena in condensed matter physics is the Meissner effect observed in superconductivity, which arises from the unique interaction between superfluids of charged particles and electromagnetic…
When supersymmetry is spontaneously broken it will be generically non-linearly realized. A method to describe the non-linear realization of supersymmetry is with constrained superfields. We discuss the basic features of this description and…
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 occurs in systems that have a lot of negative charge: the highly negatively charged $(CuO2)^{--}$ planes in the cuprates, negatively charged $(FeAs)^-$ planes in the iron arsenides, and negatively charged $B^-$ planes in…
In these lectures we review the constraints on particle physics models arising from cosmic defects. This includes constraints on theories where stable cosmic string loops, or vortons result. These can arise in supersymmetric theories. We…
We develop a unified theory to analyze the microcanonical ensembles with several constraints given by unbounded observables. Several interesting phenomena that do not occur in the single constraint case can happen under the multiple…
The thermodynamic principle of superfluid flow -- that the energy is minimized at constant entropy -- is applied to superconducting currents to derive the Meissner-Ochsenfeld effect in which magnetic fields are expelled from…
We extend a modal theory of diffraction by a set of parallel fibers to deal with the case of a hard boundary: that is a structure made for instance of air-holes inside a dielectric matrix. Numerical examples are given concerning some…
Light traveling through a liquid crystal with disclinations perceives a geometrical background which causes lensing effects similar to the ones predicted for cosmic objects like global monopoles and cosmic strings. In this article we…
The Landau problem for inhomogeneous magnetic fields is examined in a very general context and several interesting analogies with the Nielsen-Olesen vortices are established. Firstly we show that the Landau problem with non-homogeneous…
Based on the recent developed real-space theory of superconductivity (arXiv:0910.5511 and arXiv:1001.5067), we study the physical nature of the Meissner effect and London penetration depth in conventional and non-conventional…
The analisis of Pippard \cite{pip} for the growth of the normal phase into the superconducting phase in the presence of a magnetic field $H>H_c$ is applied in reverse to the case $H<H_c$ ($H_c=$critical magnetic field). We carry out the…
We theoretically evaluate changes in the magnetic potential arising from the magnetic field near superconducting thin films. An example of an atom chip based on a three-wire configuration has been simulated in the superconducting and the…
Extremal black holes tend to expel magnetic and electric fields. Fields are unable to reach the horizon because the length of the black hole throat blows up in the extremal limit. The length of the throat is related to the amount of…
Magnetic flux trapping in the Meissner transition of superconducting radio frequency cavities can substantially increase dissipation which impacts cryogenic costs and necessitates expensive magnetic shielding. Recent findings point at the…