Fabrication of binary FeSe superconducting wires by novel diffusion   process
  We report successful fabrication of multi- and mono-core FeSe wires with high transport critical current density Jc using a simple in-situ Fe-diffusion process based on the powder-in-tube (Fe-diffusion PIT) method. The seven-core wire showed transport Jc of as high as 1027 A/cm2 at 4.2 K. The superconducting transition temperature Tczero was observed at 10.5 K in the wire-samples, which is about 2 K higher than that of bulk FeSe. The Fe-diffusion PIT method is suitable for fabricating multi-core wires of the binary FeSe superconductors with superior properties. 
Toshinori Ozaki, Keita Deguchi, Yoshikazu Mizuguchi, Yasuna Kawasaki,   Takayoshi Tanaka, Takahide Yamaguchi, Hiroaki Kumaku...
cond-mat.supr-con