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Coexistence of a nearly spin-singlet state and antiferromagnetic long-range order in quantum spin system Cu$_2$CdB$_2$O$_6$

Masashi Hase·Masanori Kohno·Hideaki Kitazawa·Osamu Suzuki·Kiyoshi Ozawa·Giyuu Kido·Motoharu Imai·Xiao Hu
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Abstract

A 1/2 magnetization plateau in magnetic fields above 23 T and antiferromagnetic (AF) long-range order (AFLRO) in low fields were found in Cu$_2$CdB$_2$O$_6$. Experimental results agree with quantum Monte Carlo results for an expected spin system. There are two kinds of Cu sites [Cu(1) and Cu(2)], which are located adjacent to each other. Unexpectedly, spins on the Cu(1) and Cu(2) sites are in a nearly spin-singlet state and form AFLRO, respectively, although interactions between the Cu(1) and Cu(2) spins cannot be ignored. Cu$_2$CdB$_2$O$_6$ is the first material which shows such coexistence in an atomic scale.

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Masashi Hase, Masanori Kohno, Hideaki Kitazawa, Osamu Suzuki, Kiyoshi Ozawa, Giyuu Kido, Motoharu Imai, Xiao Hu. 2005-09-05. Coexistence of a nearly spin-singlet state and antiferromagnetic long-range order in quantum spin system Cu$_2$CdB$_2$O$_6$. https://doi.org/10.1103/physrevb.72.172412

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