Dynamic Scaling at the Zero-field 2D Superconducting Transition

TL;DR

This paper investigates the zero-field 2D superconducting transition in a thin Bi-based crystal, using dynamical scaling analysis to clarify the nature of the transition and estimate critical exponents, supported by a simple theoretical model.

Contribution

It introduces a dynamical scaling approach to analyze the 2D superconducting transition, providing new insights and estimating the dynamical critical exponent z around 5.6.

Findings

Dynamical scaling analysis clarifies the transition behavior.

Estimated dynamical critical exponent z ≈ 5.6.

Supported by data from other 2D superconductors.

Abstract

Zero-field current-voltage (I-V) characteristics of a thin ("two-dimensional") $Bi_2Sr_2CaCu_2O_{8+\delta}$ crystal are reported and analyzed in two ways. The "conventional" approach yields ambiguous results while a dynamical scaling analysis offers new insights into the Kosterlitz-Thouless-Berezinskii transition. The scaling theory predicts that the universal jump of the $I$-$V$ exponent $\alpha$ should be between $z+1$ and 1. A value of $z \simeq 5.6$ is obtained for the dynamical critical exponent, and is corroborated by data from other 2D superconductors. A simple dynamical model is presented to account for the results.