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arXiv · 1610.08157

Impact of Fe site Co substitution on superconductivity of Fe1-xCoxSe0.5Te0.5 (x = 0.0 to 0.10): A flux free single crystal study

P. K. Maheshwari·Bhasker Gahtori·Anurag Gupta·V. P. S. Awana
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Abstract

We report synthesis of Co substitution at Fe site in Fe1-xCoxSe0.5Te0.5 (x=0.0 to 0.10) single crystals via vacuum shield solid state reaction route using flux free method. Single crystal XRD results showed that these crystals grow in (00l) plane i.e., orientation in c-direction. All the crystals possess tetragonal structure having P4/nmm space group. Detailed scanning electron microscopy (SEM) images show that the crystals are grown in slab-like morphology. The EDAX results revealed the final elemental composition to be near stoichiometric. Powder X-Ray diffraction (PXRD) Rietveld analysis results show that (00l) peaks are shifted towards higher angle with increasing Co concentration. Both a and c lattice parameters decrease with increasing Co concentration in Fe1-xCoxSe0.5Te0.5 (x=0.0 to 0.10) single crystals. Low temperature transport and magnetic measurements show that the superconducting transition temperature (Tc), decreases from around 12K to 10K and 4K for x=0.03 and x=0.05 respectively. For x=0.10 crystal superconductivity is not observed down to 2K.

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P. K. Maheshwari, Bhasker Gahtori, Anurag Gupta, V. P. S. Awana. 2016-10-26. Impact of Fe site Co substitution on superconductivity of Fe1-xCoxSe0.5Te0.5 (x = 0.0 to 0.10): A flux free single crystal study. https://arxiv.org/abs/1610.08157

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