Dynamical instability of the electric transport in strongly fluctuating superconductors

TL;DR

This paper develops a theoretical framework to analyze how thermal fluctuations affect electric transport in superconductors beyond linear response, revealing reentrant behavior and instability regions across different dimensions.

Contribution

It introduces a self-consistent Gaussian approximation within the time-dependent Ginzburg-Landau theory to study nonlinear transport phenomena in fluctuating superconductors.

Findings

Reentrant S-shaped I-V curves under certain conditions

Identification of an unstable region below a critical temperature T*

Application of theory to nanowires and 2D superconductors

Abstract

Theory of the influence of the thermal fluctuations on the electric transport beyond linear response in superconductors is developed within the framework of the time dependent Ginzburg - Landau approach. The I - V curve is calculated using the dynamical self - consistent gaussian approximation. Under certain conditions it exhibits a reentrant behaviour acquiring an S - shape form. The unstable region below a critical temperature $T^{\ast }$ is determined for arbitrary dimensionality ($D=1,2,3$) of the thermal fluctuations. The results are applied to analyse the transport data on nanowires and several classes of 2D superconductors: metallic thin films, layered and atomically thick novel materials.