A PEAK IN THE BOSE GLASS LINE AT THE FIRST MATCHING FIELD OF NANOSTRUCTURES OF PINNING SITES

Abstract

Using an extensive series of molecular dynamic simulations on driven vortex lattices interacting with nanostructures of periodic square arrays of pinning sites of fixed density, we have obtained the B–T phase diagram representing a Bose glass to vortex liquid-phase transition. In solving the over damped equation of vortex motion, we took into account the vortex–vortex repulsion interaction, the attractive vortex–pinning interaction, and the driving Lorentz force at several values of temperature. We have found that the location of the Bose glass line (TBG-line) depends on the pinning strength of the pinning sites. We have also found that for each pinning strength value, there is an interesting peak of the TBG-line that occurs at the first matching field when the number of vortices equals the number of pinning sites in the sample.