Vortex plastic flow, local flux density, magnetization hysteresis loops, and critical current, deep in the Bose-glass and Mott-insulator regimes

We present simulations of flux-gradient-driven superconducting vortices interacting with strong columnar pinning defects as an external field H(t) is quasistatically swept from zero through a matching field B-phi. We analyze several measurable quantities, including the local flux density B(x,y,H(t)), magnetization M(H(t)), critical current J(c)(B(t)), and the individual vortex flow paths. We find a significant change in the behavior of these quantities as the local flux density crosses B-phi, and quantify it for many microscopic pinning parameters. Further, we find that for a given pin density J(c)(B) can be enhanced by maximizing the distance between the pins for B<B-phi.