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Singlet Ground State and Magnetization Plateaus in Ba$_3$Mn$_2$O$_8$

M. Uchida·H. Tanaka·M. Bartashevich·T. Goto
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Abstract

Magnetic susceptibility and the magnetization process have been measured in \green polycrystal. In this compound, the magnetic manganese ion exists as Mn$^{5+}$ in a tetrahedral environment, and thus the magnetic interaction can be described by an S=1 Heisenberg model. The ground state was found to be a spin singlet with an excitation gap $Δ/k_{\rm B}=11.2$ K. Magnetization plateaus were observed at zero and at half of the saturation magnetization. These results indicate that the present system can be represented by a coupled antiferromagnetic dimer model.

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M. Uchida, H. Tanaka, M. Bartashevich, T. Goto. 2001-04-24. Singlet Ground State and Magnetization Plateaus in Ba$_3$Mn$_2$O$_8$. https://doi.org/10.1143/jpsj.70.1790

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