相关论文: Fluctuation Phenomena in Superconductors
In this article the Ginzburg-Landau theory ideas are considered in their application to the description of fluctuations influence on the superfluid density in superconductor. The conclusion about the availability of two incompatible…
We present a general interpolation theory for the phenomenological effects of thermal fluctuations in superconductors. Fluctuations are described by a simple gauge invariant extension of the gaussian effective potential for the…
A theory of fluctuations in two-band superconductor MgB$_{2}$ is developed. Since the standard Ginzburg-Landau (GL) approach fails in description of its properties, we generalize it basing on the microscopic theory of a two-band…
A systematic treatment of the magnetic fluctuations effect on the properties of the normal-to-superconducting phase transition in a zero external magnetic field is given within the self-consistent approximation and the quasi-macroscopic…
A theory of critical fluctuations in extreme type-II superconductors subjected to a finite but weak external magnetic field is presented. It is shown that the standard Ginzburg-Landau representation of this problem can be recast, with help…
Gauge effects on the fluctuation properties of the normal-to-superconducting phase transition in bulk and thin film superconductors are reviewed. Similar problems in the description of other natural systems (liquid crystals, quantum field…
We review recent work on a continuum, classical theory of thermal fluctuations in two dimensional superconductors. A functional integral over a Ginzburg-Landau free energy describes the amplitude and phase fluctuations responsible for the…
We study the effect of a strong electric field on the fluctuation conductivity within the time-dependent Ginzburg-Landau theory for the case of arbitrary dimension. Our results are based on the analytical derivation of the velocity…
We first summarize our recent observations, through magnetization measurements in different low-Tc superconductors, of a rather sharp disappearance of the superconducting fluctuations in the normal state when the magnetic field approaches…
By using a Ginzburg-Landau functional in the Gaussian approximation, we calculate the energy of superconducting fluctuations above the transition, at zero external magnetic field, of a system composed by a small number $N$ of parallel…
We consider the interaction between the Earth's gravitational field and a superconductor in the fluctuation regime. Exploiting the weak field expansion formalism and using time dependent Ginzburg-Landau formulation, we show a possible…
Em geral, quando a teoria fenomenol\'ogica de Ginzburg-Landau para supercondutores \'e trabalhada, pouco se esclarece aos alunos sobre a origem da mesma. Esta tem como base conceitos termodin\^amicos como fen\^omenos cr\'iticos e…
We study the superconducting instability in systems with long but finite ranged, attractive, pairing interactions. We show that such long-ranged superconductors exhibit a new class of fluctuations in which the internal structure of the…
Classic and recent results for gauge effects on the properties of the normal-to-superconducting phase transition in bulk and thin film superconductors are reviewed. Similar problems in the description of other natural systems (liquid…
We study the behaviour of a superconductor in a weak static gravitational field for temperatures slightly greater than its transition temperature (fluctuation regime). Making use of the time-dependent Ginzburg-Landau equations, we find a…
In a two-band superconductor, two qualitatively different fluctuation modes related to the gap modules contribute to free energy and heat capacity, in addition to the phase fluctuations. The first mode has divergent temperature behaviour…
The paper deals with the study of superfluidity by a Ginzburg-Landau model that investigates the material by a second order phase transition, in which any particle has simultaneouly a normal and superfluid motion. This pattern is able to…
In the first part of this work an overview of the available data on the paramagnetic effect recently discovered in superconductors was given as well as a possible explanation of the effect. Here the consequences caused by this weakly…
Recent measurements of fluctuation diamagnetism in high temperature superconductors show distinct features above and below Tc, which can not be explained by simple gaussian fluctuation theory. Self consistent calculation of magnetization in…
Superconducting transitions are driven by thermal fluctuations close to the transition temperature, Tc. These fluctuations are averaged out in global measurements, leaving imprints on susceptibility and resistance measurements. Here, we use…