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arXiv · 0906.1508

EuFe_2As_2 magnetic structure determination

Javier Herrero-Martin·Valerio Scagnoli·Claudio Mazzoli·Yixi Su·Ranjal Mittal·Y. Xiao·Th. Brückel·Neeraj Kumar·S. K. Dhar·A. Thamizhavel·Luigi Paolasini
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Abstract

Magnetic resonant X ray scattering experiments have been performed on a single crystal of EuFe_2As_2 at the Eu L_3 absorption edge. This has permitted us to determine for the first time the orientation of Eu magnetic moments in the antiferromagnetic ordered phase below T_N=19 K as parallel to the a-axis. In addition, non-resonant magnetic X ray measurements indicate that Fe magnetic moments align along the same direction in the spin density wave phase (T<T_S~190 K). Temperature dependences indicate that the onset of the Eu AFM phase barely affects the Fe magnetic sublattice.

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Javier Herrero-Martin, Valerio Scagnoli, Claudio Mazzoli, Yixi Su, Ranjal Mittal, Y. Xiao, Th. Brückel, Neeraj Kumar, S. K. Dhar, A. Thamizhavel, Luigi Paolasini. 2009-09-23. EuFe_2As_2 magnetic structure determination. https://arxiv.org/abs/0906.1508

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