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Field-Induced Two-Step Phase Transitions in the Singlet Ground State Triangular Antiferromagnet CsFeBr$_3$

Y. Tanaka·H. Tanaka·T. Ono·A. Oosawa·K. Morishita·K. Iio·T. Kato·H. Aruga Katori·M. Bartashevich·T. Goto
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Abstract

The ground state of the stacked triangular antiferromagnet CsFeBr$_3$ is a spin singlet due to the large single ion anisotropy $D(S^z)^2$. The field-induced magnetic ordering in this compound was investigated by the magnetic susceptibility, the magnetization process and specific heat measurements for an external field parallel to the $c$-axis. Unexpectedly, two phase transitions were observed in the magnetic field $H$ higher than 3 T. The phase diagram for temperature versus magnetic field was obtained. The mechanism leading to the successive phase transitions is discussed.

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Y. Tanaka, H. Tanaka, T. Ono, A. Oosawa, K. Morishita, K. Iio, T. Kato, H. Aruga Katori, M. Bartashevich, T. Goto. 2001-08-08. Field-Induced Two-Step Phase Transitions in the Singlet Ground State Triangular Antiferromagnet CsFeBr$_3$. https://doi.org/10.1143/jpsj.70.3068

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