Microstructural refinement and enhanced transport properties in binary doped NdFeAsO superconductor

作者：Aswathy P M; Anooja J B; Varghese Neson; Syamaprasad U^*

来源：Journal of Applied Physics, 2014, 115(5): 053903.

DOI：10.1063/1.4863182

We report the synthesis of Nd1-xCaxFeAsO1-2xF2x superconductors using CaF2 as a binary dopant that provides both holes and electrons by simultaneous substitution of Ca2+ ions and F- ions at Nd3+ and O2- sites, respectively. The sample with x = 0.2 exhibits a maximum critical temperature (T-C) of 52.3 K and transport critical current density (J(C)) of 1240 A/cm(2) at 12 K. An interesting feature observed for binary doped samples is the preferential alignment of (00l) planes and the refinement of microstructure both in terms of grain size and grain connectivity. NdFeAsO based superconductors are already known for their very high critical fields and field independent J(C)(H) performance. However, the development of the bulk superconductors with oriented large grains and good grain connectivity has not been reported so far and hence the present work will be definitely a step towards the progress in NdFeAsO based conductor development.

• 出版日期2014-2-7