Inter- and intra-granular currents, Jcinter and Jcintra, in LaFePO0.94F0.06 polycrystalline sample are evaluated by measuring the remanent-state field profile using magneto-optical imaging method. Obtained images show the absence of magnetic field modulation associated with the weak-link nature of grain boundaries, indicating that Jcinter and Jc intra are comparable in magnitude in contrast to other iron-arsenide superconductors. Jcinter is estimated to be 2 × 104 A/cm2 in the limit of T= 0 K, which is larger than the values in other iron-arsenide superconductors. Implication of these J c behavior is discussed in relation with possible pairing symmetries.
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