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arXiv · 1009.4896

Fishtail effect and vortex dynamics in LiFeAs single crystals

A. K. Pramanik·L. Harnagea·C. Nacke·A. U. B. Wolter·S. Wurmehl·V. Kataev·B. Büchner
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Abstract

We investigate the fishtail effect, critical current density ($J_c$) and vortex dynamics in LiFeAs single crystals. The sample exhibits a second peak (SP) in the magnetization loop only with the field $||$ c-axis. We calculate a reasonably high $J_c$, however, values are lower than in 'Ba-122' and '1111'-type FeAs-compounds. Magnetic relaxation data imply a strong pinning which appears not to be due to conventional defects. Instead, its behavior is similar to that of the triplet superconductor Sr$_2$RuO$_4$. Our data suggest that the origin of the SP may be related to a vortex lattice phase transition. We have constructed the vortex phase diagram for LiFeAs on the field-temperature plane.

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A. K. Pramanik, L. Harnagea, C. Nacke, A. U. B. Wolter, S. Wurmehl, V. Kataev, B. Büchner. 2010-09-24. Fishtail effect and vortex dynamics in LiFeAs single crystals. https://doi.org/10.1103/physrevb.83.094502

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