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arXiv 1102.19332011-02-09cond-mat.supr-con

Magnetoelastic Coupling in the Phase Diagram of Ba1-xKxFe2As2

Sevda Avci, Omar Chmaissem, Eugene A. Goremychkin, Stephan Rosenkranz, John-Paul Castellan, Duck-Young Chung, Ilya S. Todorov, John A. Schlueter, Helmut Claus, … 展开作者

Sevda Avci, Omar Chmaissem, Eugene A. Goremychkin, Stephan Rosenkranz, John-Paul Castellan, Duck-Young Chung, Ilya S. Todorov, John A. Schlueter, Helmut Claus, Mercouri G. Kanatzidis, Aziz Daoud-Aladine, Dmitry Khalyavin, Raymond Osborn

备注：: 4 pages, 5 figures
发表信息：: Phys. Rev. B 83, 172503 (2011)
DOI：: 10.1103/PhysRevB.83.172503

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英文摘要：

We report a high resolution neutron diffraction investigation of the coupling of structural and magnetic transitions in Ba1xKxFe2As2. The tetragonal-orthorhombic and antiferromagnetic transitions are suppressed with potassium-doping, falling to zero at x <~ 0.3. However, unlike Ba(Fe1xCox)2As2, the two transitions are first-order and coincident over the entire phase diagram, with a biquadratic coupling of the two order parameters. The phase diagram is refined showing that the onset of superconductivity is at x = 0.133 with all three phases coexisting until x >~ 0.24.

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