- Jan Moudřík: Magnetic properties of a novel CeCo0.715Si2.285 compound
- 18. 3. 2015, 14:50
- lecture room F2, first floor Ke Karlovu 5
- more information
Abstract:
We report on the basic physical properties of a novel CeCo0.715Si2.285 compound, mainly its rich magnetic phase diagram. Two crystals differing slightly in occupation of a Co/Si site have been prepared and results of their characterization will be discussed. The compound crystallizes in the I-4m2 space group structure with extremely elongated unit cell (a = 4.12 Ǻ, c = 32.84 Ǻ) containing BaAl4 structural patterns typical for ternary Cerium compounds [1,2]. It orders antiferromagnetically at TN = 10.0K. Under application of a magnetic field along the c-axis it manifests numerous magnetic transitions in small fields (B < 500mT), resembling the so-called "devil's staircase" behavior (e.g. CeSb [3], CeCoGe3 [1]). Above 1 T the magnetization is almost constant up to 14T (maximum magnetic field applied within our study) but considerably reduced (0.3 mB/Ce) with respect to the free Ce3+ ion. After removing the applied field, however, the high field state remains unchanged to be removed in negative fields. The compound also exhibits strong hysteresis of magnetization with respect to varying temperature or magnetic field. For fields applied along the a-axis typical behavior for the hard axis in the material with uniaxial anisotropy is observed. Preliminary results of first single-crystal neutron diffraction experiments will be reported as well.
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[3] J. Rossat-Mignod et al., JMMM 52, 111 (1985)