Fig. 5
From: Unique defect structure and advantageous vortex pinning properties in superconducting CaKFe4As4
Temperature dependence of pinning force density fp. a fp (~ΔEcξ, green curve) calculated for non-SC defects where Ecdefect = 0 (red curve), i.e., ΔEc = Ec1144 (black curve). In this case, fp monotonically decreases with increasing T. b fp calculated for SC defects with Tcdefect = 25 K and Ecdefect(0)/Ec1144(0) = 0.6. ΔEc (blue dashed curve) shows a weak T dependence below Tcdefect, resulting in an enhancement of fp with increasing T
