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Title: Quadrupling the depairing current density in the iron-based superconductor SmFeAsO1–xHx
Abstract Iron-based 1111-type superconductors display high critical temperatures and relatively high critical current densitiesJc. The typical approach to increasingJcis to introduce defects to control dissipative vortex motion. However, when optimized, this approach is theoretically predicted to be limited to achieving a maximumJcof only ∼30% of the depairing current densityJd, which depends on the coherence length and the penetration depth. Here we dramatically boostJcin SmFeAsO1–xHxfilms using a thermodynamic approach aimed at increasingJdand incorporating vortex pinning centres. Specifically, we reduce the penetration depth, coherence length and critical field anisotropy by increasing the carrier density through high electron doping using H substitution. Remarkably, the quadrupledJdreaches 415 MA cm–2, a value comparable to cuprates. Finally, by introducing defects using proton irradiation, we obtain highJcvalues in fields up to 25 T. We apply this method to other iron-based superconductors and achieve a similar enhancement of current densities.  more » « less
Award ID(s):
2308979 2330562
PAR ID:
10549998
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; « less
Publisher / Repository:
Nature Materials
Date Published:
Journal Name:
Nature Materials
Volume:
23
Issue:
10
ISSN:
1476-1122
Page Range / eLocation ID:
1370 to 1378
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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