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arXiv · 1505.02542

Interplay of structure, magnetism, and superconductivity in Se substituted iron telluride with excess Fe

Dona Cherian·S. Rößler·S. Wirth·Suja Elizabeth
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Abstract

We investigated the evolution of the temperature-composition phase diagram of Fe$_{1+y}$Te upon Se substitution. In particular, the effect of Se substitution on the two-step, coupled magneto-structural transition in Fe$_{1+y}$Te single crystals is investigated. To this end, the nominal Fe excess was kept at $y$ = 0.12. For low Se concentrations, the two magneto-structural transitions displayed a tendency to merge. In spite of the high Fe-content, superconductivity emerges for Se concentrations, $x \geq$ 0.1. We present a temperature-composition phase diagram to demonstrate the interplay of structure, magnetism, and superconductivity in these ternary Fe chalcogenides.

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Dona Cherian, S. Rößler, S. Wirth, Suja Elizabeth. 2015-05-11. Interplay of structure, magnetism, and superconductivity in Se substituted iron telluride with excess Fe. https://doi.org/10.1088/0953-8984/27/20/205702

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