Study of anisotropy on dynamical behavior vortices and critical currents in type II superconducting films with Kagomé-like disorder at finite temperature for longitudinal current

Abstract

One of the most used mechanisms to increase the critical current in type II high critical temperature superconducting materials is the pinning of vortices. When a transport current J is applied and exceeds a critical value Jc, the vortices move and dissipate energy. Several efforts have been made from the experimental point of view to increase the effect of pinning in this type of material, creating structural defects using several techniques, mainly irradiation. However, the pinning mechanism is not fully understood yet and has been objecting to theoretical research trying to understand its influence on both, the critical currents and dynamical behavior of the vortex system. The goal of the present work is to calculate the critical current of a vortex system submitted to a transport current with a periodical pinning network of Kagome-like symmetry at finite temperature. The vortex system will be described by a set of Langevin equations and the trajectories and velocities will be obtained using the Molecular Dynamic technique. With the trajectories, we will be able to obtain the dynamical behavior of the vortex system, and the velocities will provide us with the critical currents. The understanding of the pinning mechanism is important because may help to discover new and more efficient superconducting materials, which is important for technological applications.(AU)