Driven flux-line lattices in the presence of weak random columnar disorder: Finite-temperature behavior and dynamical melting of moving Bose glass

TL;DR

This study uses 3D simulations to analyze the finite-temperature phase diagram of driven flux line lattices with weak columnar disorder, revealing the stability of the moving Bose glass phase and the emergence of an effective static pinning potential.

Contribution

It demonstrates the persistence of the moving Bose glass phase at high velocities and introduces a model explaining transverse field penetration in this phase.

Findings

Moving Bose glass exists up to melting into vortex liquid.

Dynamical transition to a moving vortex glass is not observed.

An effective static pinning potential explains transverse field penetration.

Abstract

We use 3D numerical simulations to explore the phase diagram of driven flux line lattices in presence of weak random columnar disorder at finite temperature and high driving force. We show that the moving Bose glass phase exists in a large range of temperature, up to its melting into a moving vortex liquid. It is also remarkably stable upon increasing velocity : the dynamical transition to the correlated moving glass expected at a critical velocity is not found at any velocity accessible to our simulations. Furthermore, we show the existence of an effective static tin roof pinning potential in the direction transverse to motion, which originates from both the transverse periodicity of the moving lattice and the localization effect due to correlated disorder. Using a simple model of a single elastic line in such a periodic potential, we obtain a good description of the transverse field penetration at surfaces as a function of thickness in the moving Bose glass phase.