The grain boundaries of iron pnictide superconductors have advantages over those of more commonly used cuprate superconductors reports a paper in Nature Communications this week. Iron pnictides have been studied extensively, and many of their advantages over cuprates have already been determined. But the additional information provided by this study could aid the development of high critical temperature superconductors that could be used to produce ‘ideal’ electric power lines with zero power consumption.

The misalignment of crystal grain boundaries, which deteriorates current densities, has previously been considered major problem in the development of high critical temperature superconductors. Hideo Hosono and co-workers investigate transport properties through well-defined bicrystal grain boundaries with different misorientation angles. They find that the current density in iron pnictides is tolerant to higher misorientation angles than in cuprates.