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arXiv · 1607.01093

Unique magnetic structure of YbCo$_2$Si$_2$

N. Mufti·K. Kaneko·A. Hoser·M. Gutmann·C. Geibel·C. Krellner·O. Stockert
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Abstract

We report on the results of powder and single crystal neutron diffraction to investigate the magnetic order in YbCo$_2$Si$_2$ below the N\'eel temperature $T_{\rm N} = 1.7~$K in detail. Two different magnetically ordered phases can clearly be distinguished. At lowest temperatures a commensurate magnetic structure with a propagation vector ${\bf k}_1 = (0.25~ 0.25~ 1)$ is found, while the intermediate phase ($T > 0.9~$K) is characterized by an incommensurate magnetic structure with ${\bf k}_2 = (0.25~ 0.086~ 1)$. The magnetic structure in YbCo$_2$Si$_2$ is in marked contrast to all other known RCo$_2$Si$_2$ compounds (R = rare earth element) likely due to some itineracy of the Yb 4f states being responsible for the magnetism.

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N. Mufti, K. Kaneko, A. Hoser, M. Gutmann, C. Geibel, C. Krellner, O. Stockert. 2016-07-05. Unique magnetic structure of YbCo$_2$Si$_2$. https://doi.org/10.1103/physrevb.94.045116

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