We report on experiments probing the evolution of a vortex state in response to a driving current in 2H-NbSe2 crystals. By following the vortex motion with fast transport measurements we find that the current enables the system to reorganize and access new configurations. During this process the system exhibits a long-term memory: if the current is turned off the vortices freeze in place remembering their prior motion. When the current is restored the motion resumes where it stopped. The experiments provide evidence for a dynamically driven structural change of the vortex lattice and a corresponding dynamic phase diagram that contains a previously unknown regime where the critical current can be either increased or decreased by applying an appropriate driving current.
@article{arxiv.cond-mat/9904141,
title = {Flow Induced Organization and Memory of a Vortex Lattice},
author = {Z. L. Xiao and E. Y. Andrei and M. J. Higgins},
journal= {arXiv preprint arXiv:cond-mat/9904141},
year = {2009}
}