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arXiv · 1405.3086

Local structural distortions and their role in superconductivity in SmFeAsO$_{1-x}$F$_x$ superconductors

Kapil Ingle·K. R. Priolkar·Anand Pal·V. P. S. Awana·S. Emura
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Abstract

EXAFS studies at the As K edge as a function of temperature have been carried out in SmFeAsO$_{1-x}$F$_x$ ($x$ = 0 and 0.2) compounds to understand the role of local structural distortions superconductivity observed in F doped compound. A significant correlation between thermal variation of local structural parameters like anion height and superconducting onset is found in the fluorinated compound. Such a variation in anion height is absent in non-superconducting compound. Increase in Fe-As bond distance just below superconducting onset temperature indicates a similarity in distortions observed in high T$_C$ cuprates and these Fe based superconductors.

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Kapil Ingle, K. R. Priolkar, Anand Pal, V. P. S. Awana, S. Emura. 2014-05-13. Local structural distortions and their role in superconductivity in SmFeAsO$_{1-x}$F$_x$ superconductors. https://doi.org/10.1088/0953-2048%2F27%2F7%2F075010

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