We report the lower critical fields Hc1 measurements using a miniature Hall-sensor array on superconducting iron-pnictide PrFeAsO 1-y single crystals. The local magnetic induction measured by the sensor at the edge of the crystal clearly resolves the first flux penetration from the Meissner state. The temperature dependence of Hc1 for H c is well scaled by the in-plane superfluid density determined by the penetration depth measurements. The anisotropy of Hc1 at low temperatures is estimated to be ≃2.5, which is smaller than the anisotropy of the upper critical fields Hc2, indicating the multiband superconductivity in this system where the active band for superconductivity is more two-dimensional.
- Lower critical field
- Penetration depth
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering