Topological Defect Densities in Type-I Superconducting Phase Transitions

In this work we address the impact of a cubic term addition to the Ginzburg-Landau mean-field potential, and study the consequences on the description of first order phase transitions in superconductors. Constraints are obtained from experiment and used to assess consequences on topological defect creation. No fundamental changes in either the Kibble-Zurek or Hindmarsh-Rajantie predictions are found.

The Kibble-Zurek mechanism (KZM) describes the non-equilibrium dynamics and topological defect formation in systems undergoing second-order phase transitions. KZM has found applications in fields such as cosmology and condensed matter physics. However, it is generally not suitable for describing first-order phase transitions. It has been demonstrated that transitions in systems like superconductors or charged superfluids, typically classified as second-order, can exhibit weak...

Kibble-Zurek scaling is the scaling of the density of the topological defects formed via the Kibble-Zurek mechanism with respect to the rate at which a system is cooled across a continuous phase transition. Recently, the density of the topological defects formed via the Kibble-Zurek mechanism was computed for a system cooled through a first-order phase transition instead of the usual continuous transitions. Here we address the problem of whether such defects generated across ...

In superconductors, and in other systems with a local U(1) gauge invariance, there are two mechanisms that form topological defects in phase transitions. In addition to the standard Kibble mechanism, thermal fluctuations of the magnetic field also lead to defect formation. This mechanism is specific to local gauge theories, predicts a qualitatively different spatial defect distribution and is the dominant source for topological defects in slow transitions. I review the argume...

A recent experiment that sees the spontaneous creation of magnetic flux on quenching high-$T_c$ films has shown that earlier null results were a consequence of the lack of saturation of the Zurek-Kibble causal bounds against which flux density was measured. In this letter we estimate how efficient the production of topological charge is in planar systems, both for the aforementioned experiment (when flux measures topological charge) and for an earlier experiment on planar liq...

In this Comment, we show that the paper by Qi Li, D. Belitz and J. Toner, published in Phys. Rev. B {\bf 79}, 054514 (2009), contains an incomplete mean-field analysis of a simple model of Ginzburg-Landau type. The latter contains a stable non-unitary phase, which has not been found in this study and is missing in the outlined picture of possible stable phases. In this Comment, the mean field analysis has been corrected, the errors have been explained in details and relevant ...

When a symmetry gets spontaneously broken in a phase transition, topological defects are typically formed. The theoretical picture of how this happens in a breakdown of a global symmetry, the Kibble-Zurek mechanism, is well established and has been tested in various condensed matter experiments. However, from the viewpoint of particle physics and cosmology, gauge field theories are more relevant than global theories. In recent years, there have been significant advances in th...

In recent years, there were a number of experimental developments and discoveries of novel superconducting materials which exhibit multicomponent, many-body degrees of freedom. These superconductors, that are described by several superconducting condensates, feature many new interesting phenomena that are absent in their single-component counterparts. Several of these new aspects of multicomponent superconductivity are addressed in this report.

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 transi\c{c}\~oes de fase que, se devidamente tratados, enriquecem de sobremaneira a aula sobre tal assunto. Assim, neste trabalho apresentamos uma sequ\^encia para o desenvolvimento da principal teoria fenomenol\'ogica da supercondutividade. Iniciamo...

We propose a new mechanism for formation of topological defects in a U(1) model with a local gauge symmetry. This mechanism leads to definite predictions, which are qualitatively different from those of the Kibble-Zurek mechanism of global theories. We confirm these predictions in numerical simulations, and they can also be tested in superconductor experiments. We believe that the mechanism generalizes to more complicated theories.