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arXiv · 2205.07005

S=2 Quantum Spin Chain with the Biquadratic Exchange Interaction

Tôru Sakai·Takaharu Yamada·Ryosuke Nakanishi·Rito Furuchi·Hiroki Nakano·Hirono Kaneyasu·Kiyomi Okamoto·Takashi Tonegawa
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Abstract

The $S=2$ quantum spin chain with the single-ion anisotropy $D$ and the biquadratic exchange interaction $J_{\rm BQ}$ is investigated using the numerical diagonalization of finite-size clusters and the level spectroscopy analysis. It is found that the intermediate-$D$ phase corresponding to the symmetry protected topological (SPT) phase appears in a wide region of the ground state phase diagram. We also obtain the phase diagram at the half of the saturation magnetization which includes the SPT plateau phase.

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Tôru Sakai, Takaharu Yamada, Ryosuke Nakanishi, Rito Furuchi, Hiroki Nakano, Hirono Kaneyasu, Kiyomi Okamoto, Takashi Tonegawa. 2022-05-14. S=2 Quantum Spin Chain with the Biquadratic Exchange Interaction. https://doi.org/10.7566/jpsj.91.074702

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