Structural phase transition in TmxFe1-xSe0.85 (Tm = Mn and Cu) and its relation to superconductivity

Tzu-Wen Huang; Ta-Kun Chen; Kuo-Wei Yeh; Chung-Ting Ke; Chi Liang Chen; Yi-Lin Huang; Fong-Chi Hsu; Maw-Kuen Wu; Phillip M. Wu; Maxim Avdeev; Andrew J. Studer

arXiv · 0907.4001

Structural phase transition in TmxFe1-xSe0.85 (Tm = Mn and Cu) and its relation to superconductivity

Tzu-Wen Huang·Ta-Kun Chen·Kuo-Wei Yeh·Chung-Ting Ke·Chi Liang Chen·Yi-Lin Huang·Fong-Chi Hsu·Maw-Kuen Wu·Phillip M. Wu·Maxim Avdeev·Andrew J. Studer

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Abstract

In this letter, we report the results of detailed studies on Mn- and Cu-substitution to Fe-site of beta-FeSe, namely MnxFe1-xSe0.85 and CuxFe1-xSe0.85. The results show that with only 10 at% Cu-doping the compound becomes a Mott insulator. Detailed temperature dependent structural analyses of these Mn- and Cu-substituted compounds show that the structural transition, which is associated with the changes in the building block FeSe4 tetrahedron, is essential to the occurrence of superconductivity in beta-FeSe.

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Tzu-Wen Huang, Ta-Kun Chen, Kuo-Wei Yeh, Chung-Ting Ke, Chi Liang Chen, Yi-Lin Huang, Fong-Chi Hsu, Maw-Kuen Wu, Phillip M. Wu, Maxim Avdeev, Andrew J. Studer. 2009-07-23. Structural phase transition in TmxFe1-xSe0.85 (Tm = Mn and Cu) and its relation to superconductivity. https://arxiv.org/abs/0907.4001

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