Vortex localization in single crystals of Tl2Ba2CuO6+ delta with columnar defects

Critical current peaks at 3Bphi in superconductors with columnar defects: recrystallizing the interstitial glass

The role of commensurability and the interplay of correlated disorder and interactions on vortex dynamics in the presence of columnar pins is studied via molecular dynamics simulations. Simulations of dynamics reveal substantial caging effects and a nonmonotonic dependence of the critical current with enhancements near integer values of the matching field Bphi and 3Bphi in agreement with experiments on the cuprates. We find qualitative differences in the phase diagram for small and large values of the matching field.