Superconductivity of powder-in-tube Sr0.6K0.4Fe2As2 wires

Nb-sheathed Sr0.6K0.4Fe2As2 superconducting wires have been fabricated using the powder-in-tube (PIT) method for the first time and the superconducting properties of the wires have been investigated. The transition temperature (T-c) of the Sr0.6K0.4Fe2As2 wires is confirmed to be as high as 35.3 K. Most importantly, Sr0.6K0.4Fe2As2 wires exhibit a very weak J(c)-field dependence behavior even the temperature is very close to T-c. The upper critical field H-c2(0) value can exceed 140T, surpassing those of MgB2 and all the low temperature superconductors. Such high H-c2 and superior J(c)-field performance make the 122 phase SrKFeAs wire conductors a powerful competitor potentially useful in very high field applications. (c) 2009 Elsevier B.V. All rights reserved.