Anisotropic flux penetration into amorphous Mo80Ge20 square networks

Abstract

We have investigated anisotropic flux penetrations into superconducting amorphous Mo80Ge20 square networks by using a magneto-optical imaging method. Pinning force dependence of the anisotropy is investigated by changing the fabrication process of the Mo80Ge20 thin films. Diagonal flux penetration becomes more dominant with less pinning sites, which is consistent with the earlier prediction with the time-dependent Ginzburg–Landau simulation with an assumption of pinning-force free in superconducting region. These results strongly indicate that the diagonal flux penetration in the square superconducting networks with weak pinning is intrinsic.