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Magnetic phase diagram of antiferroquadrupole ordering in HoB2C2

Tatsuya Yanagisawa·Terutaka Goto·Yuichi Nemoto·Ryuta Watanuki·Kazuya Suzuki·Osamu Suzuki·Giyuu Kido
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Abstract

The magnetic phase diagram for antiferro-quadrupole (AFQ) ordering in tetragonal HoB$_2$C$_2$ has been investigated by measurements of elastic constants $C_{11}$, $C_{44}$ and $C_{66}$ in fields along the basal $x$-$y$ plane as well as the principal [001]-axis. The hybrid magnet (GAMA) in Tsukuba Magnetic Laboratory was employed for high field measurements up to 30 T. The AFQ phase is no longer observed above 26.3 T along the principal [001] axis in contrast to the relatively small critical field of 3.9 T in fields applied along the basal [110] axis. The quadrupolar intersite interaction of $O_{xy}$ and/or $O_2^2$ is consistent with the anisotropy in the magnetic phase diagram of the AFQ phase in HoB$_2$C$_2$.

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Tatsuya Yanagisawa, Terutaka Goto, Yuichi Nemoto, Ryuta Watanuki, Kazuya Suzuki, Osamu Suzuki, Giyuu Kido. 2005-01-20. Magnetic phase diagram of antiferroquadrupole ordering in HoB2C2. https://doi.org/10.1103/physrevb.71.104416

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