Impurity Effects On The Transport-Properties Of 2-Dimensional Magnetic Vortex Systems

We study the dynamics of two-dimensional magnetic vortex systems with a transport current. The dynamics for interacting vortices in random media is described in terms of the Langevin-type stochastic equation. By changing the impurity strength and magnetic induction as well as temperature, we discuss the relationship between the transport current and the induced average vortex velocity. The present results for the I-V curve are found to be consistent with those of recent experiments in amorphous superconducting thin films.