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arXiv · 0901.0738

Neutron scattering investigation of the magnetic order in single crystalline BaFe2As2

M. Kofu·Y. Qiu·Wei Bao·S. -H. Lee·S. Chang·T. Wu·G. Wu·X. H. Chen
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Abstract

The magnetic structure of BaFe2As2 was completely determined from polycrystalline neutron diffraction measurements soon after the ThCr2Si2-type FeAs-based superconductors were discovered. Both the moment direction and the in-plane antiferromagnetic wavevector are along the longer a-axis of the orthorhombic unit cell. There is only one combined magnetostructural transition at about 140 K. However, a later single-crystal neutron diffraction work reported contradicting results. Here we show neutron diffraction results from a clean single crystal sample, grown by a self-flux method, that support the original polycrystalline work.

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M. Kofu, Y. Qiu, Wei Bao, S. -H. Lee, S. Chang, T. Wu, G. Wu, X. H. Chen. 2009-01-07. Neutron scattering investigation of the magnetic order in single crystalline BaFe2As2. https://doi.org/10.1088/1367-2630%2F11%2F5%2F055001

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