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arXiv · 0808.0474

Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide

Kuo-Wei Yeh·Tzu-Wen Huang·Yi-Lin Huang·Ta-Kun Chen·Fong-Chi Hsu·Phillip M. Wu·Yong-Chi Lee·Yan-Yi Chu·Chi-Liang Chen·Jiu-Yong Luo·Der-Chung Yan·Maw-Kuen Wu
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Abstract

We have carried out a systematic study of the PbO-type compound FeSe_{1-x}Te_x (x = 0~1), where Te substitution effect on superconductivity is investigated. It is found that superconducting transition temperature reaches a maximum of Tc=15.2K at about 50% Te substitution. The pressure-enhanced Tc of FeSe0.5Te0.5 is more than 10 times larger than that of FeSe. Interestingly, FeTe is no longer superconducting. A low temperature structural distortion changes FeTe from triclinic symmetry to orthorhombic symmetry. We believe that this structural change breaks the magnetic symmetry and suppresses superconductivity in FeTe.

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Kuo-Wei Yeh, Tzu-Wen Huang, Yi-Lin Huang, Ta-Kun Chen, Fong-Chi Hsu, Phillip M. Wu, Yong-Chi Lee, Yan-Yi Chu, Chi-Liang Chen, Jiu-Yong Luo, Der-Chung Yan, Maw-Kuen Wu. 2008-08-05. Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide. https://doi.org/10.1209/0295-5075/84/37002

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