Optimization of a Non-arsenic Iron-based Superconductor for Wire Fabrication

Jonathan E. Mitchell; Daniel A. Hillesheim; Craig A. Bridges; M. Parans Paranthaman; Kris Gofryk; Mike Rindfleisch; Mike Tomsic; Athena S. Sefat

doi:10.1088/0953-2048/28/4/045018

arXiv · 1412.3065

Optimization of a Non-arsenic Iron-based Superconductor for Wire Fabrication

Jonathan E. Mitchell·Daniel A. Hillesheim·Craig A. Bridges·M. Parans Paranthaman·Kris Gofryk·Mike Rindfleisch·Mike Tomsic·Athena S. Sefat

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Abstract

We report on the optimization of synthesis of iron-selenide (non-arsenic) superconducting powders that are based on '122' composition, with optimal Tc = 38 K and Jc = 10^5 A/cm2 (4 K). We also report on the wire proof-of concept for these materials, by producing ~ 40 ft of wire that produce Ic. The 122 selenides are more difficult to synthesize and have more complex crystal structures compared to '11' selenides (FeSe and FeSe1-xTex), but they do offer higher Tc and might provoke a natural extension for 11 work.

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Jonathan E. Mitchell, Daniel A. Hillesheim, Craig A. Bridges, M. Parans Paranthaman, Kris Gofryk, Mike Rindfleisch, Mike Tomsic, Athena S. Sefat. 2014-12-09. Optimization of a Non-arsenic Iron-based Superconductor for Wire Fabrication. https://doi.org/10.1088/0953-2048%2F28%2F4%2F045018

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