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arXiv · 2106.12126

Quantum critical phenomena in a spin-1/2 frustrated square lattice with spatial anisotropy

H. Yamaguchi·Y. Iwasaki·Y. Kono·T. Okubo·S. Miyamoto·Y. Hosokoshi·A. Matsuo·T. Sakakibara·T. Kida·M. Hagiwara
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Abstract

We present a model compound with a spin-1/2 spatially anisotropic frustrated square lattice, in which three antiferromagnetic interactions and one ferromagnetic interaction are competing. We observe an unconventional gradual increase in the low-temperature magnetization curve reminiscent of the quantum critical behavior between gapped and gapless phases. In addition, the specific heat and electron spin resonance signals indicate one-dimensional characteristics. These results demonstrate quantum critical behavior associated with one dimensionalization caused by frustrated interactions in the spin-1/2 spatially anisotropic square lattice.

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H. Yamaguchi, Y. Iwasaki, Y. Kono, T. Okubo, S. Miyamoto, Y. Hosokoshi, A. Matsuo, T. Sakakibara, T. Kida, M. Hagiwara. 2021-06-23. Quantum critical phenomena in a spin-1/2 frustrated square lattice with spatial anisotropy. https://doi.org/10.1103/physrevb.103.l220407

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