I-V Characteristics of High Temperature Superconductors with Columnar Defects

TL;DR

This paper investigates the vortex glass transition in high temperature superconductors with columnar defects through Monte Carlo simulations, revealing distinct dynamical exponents for different current directions.

Contribution

It introduces a vortex loop model to study the transition and determines two separate dynamical exponents for perpendicular and parallel current applications.

Findings

Two dynamical exponents: $z_{ot} = 6 \\pm 0.5$ and $z_{\\parallel} = 4 \\pm 0.5$.

Finite-size scaling analysis of $I$-$V$ characteristics.

Vortex glass transition behavior influenced by columnar defects.

Abstract

The vortex glass transition in the presence of columnar defects is studied by Monte Carlo simulations of a vortex loop model, suggested by the analogy to the $T=0$ superconductor-insulator transition for dirty bosons in (2+1)D. From finite-size scaling analysis of the $I$-$V$ characteristic we find two dynamical exponents describing the non-equilibrium behavior. We obtain $z_{\perp} = 6 \pm 0.5$ and $z_{\parallel} = 4 \pm 0.5$ when the current is applied perpendicular and parallel to the columnar defects respectively.