Local transport properties of PrFeAsO0.7 using FIB micro-fabrication technique

To evaluate the anisotropy of single crystals with a size of several tens of micrometers, we develop a technique for measuring the local transport properties along both the ab -plane and the c- axis using microsize devices fabricated by a focused ion beam process. We applied this technique to identify the resistivity anisotropy ( γ ρ = ρ c / ρ ab ) of the iron-pnictide superconductor PrFeAsO 0.7 synthesized under high-pressure. The obtained value of γ ρ ∼ 120 at 50 K indicates the presence of strong anisotropy, which is comparable to the anisotropy measured by other methods. The weak temperature dependence detected for the normalized resistivity along the c -axis (less than 10% difference at 280 K and 50 K) suggests a peculiar interlayer transport mechanism for PrFeAsO 0.7 .