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Magnetic Phase Diagrams with Possible Field-induced Antiferroquadrupolar Order in TbB$_2$C$_2$

Koji Kaneko·Hideya Onodera·Hiroki Yamauchi·Takuo Sakon·Mitsuhiro Motokawa·Yasuo Yamaguchi
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Abstract

Magnetic phase diagrams of a tetragonal antiferromagnet TbB$_2$C$_2$ were clarified by temperature and field dependence of magnetization. It is noticeable that the N{é}el temperature in TbB$_2$C$_2$ is anomalously enhanced with magnetic fields, in particular the enhancement reaches 13.5 K for the ${<}1 1 0{>}$ direction at 10 T. The magnetization processes as well as the phase diagrams are well interpreted assuming that there appear field-induced antiferroquadrupolar ordered phases in TbB$_2$C$_2$. The phase diagrams of the AFQ compounds in RB$_2$C$_2$ are systematically understood in terms of the competition with AFQ and AFM interactions.

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Koji Kaneko, Hideya Onodera, Hiroki Yamauchi, Takuo Sakon, Mitsuhiro Motokawa, Yasuo Yamaguchi. 2002-12-04. Magnetic Phase Diagrams with Possible Field-induced Antiferroquadrupolar Order in TbB$_2$C$_2$. https://doi.org/10.1103/physrevb.68.012401

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