Annealing effects on superconductivity in SrFe2−xNixAs2
نویسندگان
چکیده
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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