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arXiv · 0908.4095

Annealing effects on superconductivity in SrFe2-xNixAs2

Shanta R. Saha·Nicholas P. Butch·Kevin Kirshenbaum·Johnpierre Paglione
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Abstract

Superconductivity has been explored in single crystals of the Ni-doped FeAs-compound SrFe2-xNixAs2 grown by self-flux solution method. The antiferromagnetic order associated with the magnetostructural transition of the parent compound SrFe2As2 is gradually suppressed with increasing Ni concentration x and bulk-phase superconductivity with full diamagnetic screening is induced near the optimal doping of x = 0.15 with a maximum transition temperature Tc ~9.8 K. An investigation of high-temperature annealing on as-grown samples indicate that the heat treatment can enhance Tc as much as ~50 %.

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Shanta R. Saha, Nicholas P. Butch, Kevin Kirshenbaum, Johnpierre Paglione. 2009-08-27. Annealing effects on superconductivity in SrFe2-xNixAs2. https://doi.org/10.1016/j.physc.2009.11.079

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