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The Fe-based superconductors (FBS) present a large variety of compounds whoseproperties are affected to different extents by their crystal structures.Amongst them, the $\it{RE}$FeAs(O,F) ($\it{RE}$1111, where $\it{RE}$ is a rareearth element) is the family with the highest critical temperature $T_c$ butalso with a large anisotropy and Josephson vortices as demonstrated in theflux-flow regime in Sm1111 ($T_c$ $\sim$ 55 K). Here we focus our attention onthe pinning properties of the lower-$T_c$ Nd1111 in the flux-creep regime. Wedemonstrate that for H//c critical current density $J_c$ at high temperaturesis dominated by point-defect pinning centres, whereas at low temperaturessurface pinning by planar defects parallel to the $\it{c}$-axis and vortexshearing prevail. When the field approaches the $\it{ab}$-planes, two differentregimes are observed at low temperatures as a consequence of the transitionbetween 3D-Abrikosov and 2D-Josephson vortices: one is determined by theformation of a vortex staircase structure and one by lock-in of the vorticesparallel to the layers. This is the first study on FBS showing this behaviourin a full temperature, field, and angular range and it demonstrates that,despite the lower $T_c$ and anisotropy of Nd1111 with respect to Sm1111, thiscompound is substantially affected by intrinsic pinning generating a strong$\it{ab}$-peak in $J_c$.

Intrinsic and extrinsic pinning in NdFeAs(O,F): vortex trapping and lock-in by the layered structure