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arXiv · 1505.06066

Oxygen-annealing effects on superconductivity in polycrystalline Fe1-xTe1-ySey

Gina M. Friederichs·Matthias P. B. Wörsching·Dirk Johrendt
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Abstract

Superconductivity in anti-PbO-type iron chalcogenides Fe1-xTe1-ySey (x = 0, 0.1, y = 0.1 0.4) depends on the amount (x) of interstitial iron atoms located between the FeTe1-ySey layers. Non-superconducting samples of nominal Fe1.1Te1-ySey convert to superconductors with critical temperatures up to 14 K after annealing at 300°C in an oxygen atmosphere. The process is irreversible upon subsequent hydrogen annealing. Magnetic measurements are consistent with the formation of iron oxides suggesting that oxygen annealing preferably extracts interstitial iron from Fe1-xTe1-ySey which interfere with superconductivity.

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Gina M. Friederichs, Matthias P. B. Wörsching, Dirk Johrendt. 2015-05-22. Oxygen-annealing effects on superconductivity in polycrystalline Fe1-xTe1-ySey. https://arxiv.org/abs/1505.06066

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