Absence of Translational Ordering in Driven Vortex Lattices

TL;DR

This study uses molecular dynamics simulations to investigate whether a driven vortex lattice maintains translational order, finding no such order at any drive level but observing long-range orientational order at high drives.

Contribution

It demonstrates that driven vortex lattices lack translational order across all drives, contrasting with prior assumptions, and reveals a high-drive phase with orientational order.

Findings

No topological or translational order at any drive

Presence of long-range orientational order at high drives

Simulation results align qualitatively with experimental I-V characteristics

Abstract

By using finite temperature molecular dynamics simulations, we consider the question of the existence of dynamical ordering as a two dimensional vortex lattice is driven through a random background potential. The shape of the current-voltage(I-V) characteristics are qualitatively the same as those seen in experiments on the conventional superconductors 2H-NbSe_{2} and Mo_{77}Ge_{23}. However, in contrast to previous simulations, we find that the lattice has no topological or translational order for any value of the driving but that it does exhibit a high driving phase where long range orientational order exists.