Table 1. Several typical magnetization relaxation studies on IBSs.
| Sample | Tc | Results orconclusions | γ (Hc2) | ξc/d |
|---|---|---|---|---|
| Ba(Fe0.93Co0.07)2As27 (SMP) | 22 K | Collective to plastic creep crossover at Hsp | 1.5 ~ 246 | 1.9 |
| Ca(Fe1-xCox)2As2 (x = 0.056)39 (no SMP) | 19 K | Plastic creep rather than collective model | ~1.352 | / |
| Ba0.72K0.28Fe2As212 (SMP) | 32.7 K | Single to collective at Hon, collective to plastic at Hsp | 1 ~ 226 | 4.4 |
| Ca0.25Na0.75Fe2As242 (no SMP) | 33.4 K | Elastic to plastic near the upper end of power-law regime in Jc(H) (Jc ∝ H-α, α = 0.55) | ~253 | 1.6 (estimated) |
| LiFeAs14 (SMP) | 16.5 K | U0(H) peak occurs below Hsp → VL model | 1.5 ~ 2.454 | 2.7 |
| FeTe0.7Se0.315 (SMP) | 10.6 K | Collective model, SMP was associated with vortex-vortex and vortex-defect interactions | 1~227 | 4.3 |
| FeSe37 (no SMP) | 9 K | Elastic to plastic creep crossover was observed | ~1.855 | 6.3 |
| Ca0.8La0.2Fe0.978Co0.022As2 (present study) | 37.8 K | Single to collective at Hs, elastic to plastic near Hmin. | 2.7 ~ 4.2 (SI) | 0.72 (estimated) |
| SmFeAsO0.85F0.158 (polycrystalline) | 46 K | 3D flux line to 2D lattice | 4 ~ 829 | 0.21 |
γ is the upper critical field Hc2 anisotropy ratio. ξc is c-axis coherence length and d is the distance between two adjacent FeAs/FeSe layers.