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arXiv · 1808.06812

Field-enhanced quantum fuctuation in S=1/2 frustrated square lattice

H. Yamaguchi·Y. Sasaki·T. Okubo·M. Yoshida·T. Kida·M. Hagiwara·Y. Kono·S. Kittaka·T. Sakakibara·M. Takigawa·Y. Iwasaki·Y. Hosokoshi
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Abstract

We present a new model compound with the S = 1/2 frustrated square lattice composed of the charge-transfer salt (o-MePy-V)PF6. Ab initio calculations indicate the formation of an S = 1/2 square lattice, in which six types of nearest-neighbor ferromagnetic- and antiferromagnetic interactions cause frustration. By applying a magnetic field, we observe an unusually gradual increase of magnetization and a subsequent 1/2-plateau-like behavior. A numerical analysis using the tensor network method qualitatively demonstrates such behaviors and suggests a collinear ordered state and a field-enhanced quantum fluctuation. Furthermore, the local magnetization and T1^-1 probed by nuclear magnetic resonance measurements support these findings.

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H. Yamaguchi, Y. Sasaki, T. Okubo, M. Yoshida, T. Kida, M. Hagiwara, Y. Kono, S. Kittaka, T. Sakakibara, M. Takigawa, Y. Iwasaki, Y. Hosokoshi. 2018-08-21. Field-enhanced quantum fuctuation in S=1/2 frustrated square lattice. https://doi.org/10.1103/physrevb.98.094402

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