Effect of intensity and size of defect on Ginzburg-Landau free energy for type II superconductors

It has been successfully investigated the effect of intensity and size of defect on GL free energy density for type II superconductor. The investigation was carried out numerically based on the TDGL equation. The physical system under study square type II superconductor of niobium (κ = 1,3) with size 12ξ×12ξ with defects placed at the center of the material. This material is placed in a vacuum, where an external magnetic field H = 0.7Hck̂, is applied to the material. The intensity and size of the defect is varied. Its effect on the density of GL free energy is discussed based on the average curve of free energy density and the contour of the dynamics of GL free energy in the material.