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Magnetic Phase Transition and Magnetization Plateau in Cs$_2$CuBr$_4$

H. Tanaka·T. Ono·H. A. Katori·H. Mitamura·F. Ishikawa·T. Goto
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Abstract

The crystal structure of Cs$_2$CuBr$_4$ is the same as that of Cs$_2$CuCl$_4$, which has been characterized as a spin-1/2 quasi-two-dimensional frustrated system. The magnetic properties of Cs$_2$CuBr$_4$ were investigated by magnetization and specific heat measurements. The phase transition at zero magnetic field was detected at $T_{\rm N}=1.4$ K. It was observed that the magnetization curve has a plateau at about one-third of the saturation magnetization for magnetic field $H$ parallel to the $b$- and $c$-axes, while no plateau was observed for $H\parallel a$. The field-induced phase transition to the plateau state appears to be of the first order. The mechanism leading to the magnetization plateau is discussed.

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H. Tanaka, T. Ono, H. A. Katori, H. Mitamura, F. Ishikawa, T. Goto. 2002-04-05. Magnetic Phase Transition and Magnetization Plateau in Cs$_2$CuBr$_4$. https://doi.org/10.1143/ptps.145.101

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