Fig. 2.

Evolution history. (A) The evolution process starts with a superconductor without inclusions shown in the left panel. The following panels show pinning landscapes having highest $J_{\mathrm{c}}$ in first, third, fourth, sixth, ninth, 12th, and 21st generation, correspondingly. In the first generation, the maximal $J_{\mathrm{c}}$ is achieved with the configuration containing a single nearly spherical inclusion. In second and third generations, this inclusion evolves to a flattened ellipsoid lying in the plane spanned by the current and magnetic field. In subsequent generations, this ellipsoid is copied multiple times to enhance the total pinning. The remaining generations of the evolution process fine tunes the landscape by copying, removing, moving, and slightly deforming successors of the seed inclusion. (B) The final pinning landscape consisting of a periodic array of almost planar defects has the best possible $J_{\mathrm{c}}$ in the framework of our model. The positions of pinned vortices are shown schematically by blue circles. (C) The evolution tree. The numbered circles represent configurations with the maximum $J_{\mathrm{c}}$ per generation. Dead mutations are indicated by dots. All $J_{\mathrm{c}}$ values are color-coded.