Scaling determination of the nonlinear I-V characteristics for 2D superconducting networks

TL;DR

This paper uses computer simulations to analyze the nonlinear current-voltage behavior of 2D superconducting networks, confirming a specific scaling relation and addressing previous conflicting conclusions.

Contribution

It demonstrates that the nonlinear I-V exponent in 2D superconducting networks follows a finite-size scaling form supporting the relation a=z+1, clarifying previous debates.

Findings

Supports the relation a=z+1 for the nonlinear I-V exponent

Uses finite-size scaling analysis from simulations

Addresses and clarifies previous conflicting results

Abstract

It is shown from computer simulations that the current-voltage ($I$-$V$) characteristics for the two-dimensional XY model with resistively-shunted Josephson junction dynamics and Monte Carlo dynamics obeys a finite-size scaling form from which the nonlinear $I$-$V$ exponent $a$ can be determined to good precision. This determination supports the conclusion $a=z+1$, where $z$ is the dynamic critical exponent. The results are discussed in the light of the contrary conclusion reached by Tang and Chen [Phys. Rev. B {\bf 67}, 024508 (2003)] and the possibility of a breakdown of scaling suggested by Bormann [Phys. Rev. Lett. {\bf 78}, 4324 (1997)].