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Anisotropic magnetic properties of CeAg$_2$Ge$_2$ single crystal

A. Thamizhavel·R. Kulkarni·S. K. Dhar
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Abstract

In order to investigate the anisotropic magnetic properties of CeAg$_2$Ge$_2$, we have successfully grown the single crystals, for the first time, by high temperature solution growth (flux) method. We have performed a detailed study of the grown single crystals by measuring their electrical resistivity, magnetic susceptibility, magnetization, specific heat and magnetoresistance. A clear anisotropy and an antiferromagnetic transition at $T_{\rm N}$ = 4.6 K have been observed in the magnetic properties. The magnetic entropy reaches $R$ ln 4 at 20 K indicating that the ground state and the first excited state are very closely spaced (a quasi-quartet state). From the specific heat measurements and crystalline electric field (CEF) analysis of the magnetic susceptibility, we have found the level splitting energies as 5 K and 130 K. The magnetization measurements reveal that the a-axis is the easy axis of magnetization and the saturation moment is $μ_{\rm s}$ = 1.6 $μ_{\rm B}$/Ce, corroborating the previous neutron diffraction measurements on a polycrystalline sample.

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A. Thamizhavel, R. Kulkarni, S. K. Dhar. 2007-01-10. Anisotropic magnetic properties of CeAg$_2$Ge$_2$ single crystal. https://doi.org/10.1016/j.physb.2006.01.483

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