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arXiv · 2309.14619

Field-induced quantum phase in a frustrated zigzag-square lattice

Hironori Yamaguchi·Kazutoshi Shimamura·Yasuo Yoshida·Akira Matsuo·Koichi Kindo·Kiichi Nakano·Satoshi Morota·Yuko Hosokoshi·Takanori Kida·Yoshiki Iwasaki·Seiya Shimono·Koji Araki·Masayuki Hagiwara
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Abstract

This study presents the experimental realization of a spin-1/2 zigzag-square lattice in a verdazyl-based complex, namely ($m$-Py-V-2,6-F$_2$)$[$Cu(hfac)$_2]$. Molecular orbital calculations suggest the presence of five types of frustrated exchange couplings. Our observations reveal an incremental increase in the magnetization curve beyond a critical field, signifying a phase transition from the antiferromagnetic ordered state to a quantum state characterized by a 1/2 plateau. This intriguing behavior arises from the effective stabilization of a zigzag chain by the external fields. These results provide evidence for field-induced dimensional reduction in a zigzag-square lattice attributed to the effects of frustration.

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Hironori Yamaguchi, Kazutoshi Shimamura, Yasuo Yoshida, Akira Matsuo, Koichi Kindo, Kiichi Nakano, Satoshi Morota, Yuko Hosokoshi, Takanori Kida, Yoshiki Iwasaki, Seiya Shimono, Koji Araki, Masayuki Hagiwara. 2023-09-26. Field-induced quantum phase in a frustrated zigzag-square lattice. https://doi.org/10.1103/physrevmaterials.7.l091401

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