Influence of Fe Buffer Layer on Co-Doped BaFe₂As₂ Superconducting Thin Films

Figure 3

(a) Hysteresis loops obtained by means of MOKE measurements: Ba-122/Fe at 5 K (red squares) and 300 K (black squares); Ba-122 thin film at 300 K (open squares); (b) MOI on Ba-122/Fe film at room temperature. Since MOI is sensitive to out-of-plane magnetic fields, the in-plane magnetization direction can be inferred from the signal at the edges (indicated by yellow arrows). (c) MOI at low temperature ( K), after Zero-Field Cooling (ZFC) with applied magnetic field  mT; bright regions: preferential vortex penetration and normal zones; dark regions: screened zones.

(a)

(b)

(c)