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arXiv · 2404.06767

Quantum spin state stabilized by coupling with classical spins

Hironori Yamaguchi·Tsuyoshi Okubo·Akira Matsuo·Takashi Kawakami·Yoshiki Iwasaki·Taiki Takahashi·Yuko Hosokoshi·Koichi Kindo
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Abstract

We introduce a model compound featuring a spin-1/2 frustrated square lattice partially coupled by spin-5/2. A significant magnetization plateau exceeding 60 T could be observed, indicating a quantum state formed by $S$ = 1/2 spins in the square lattice. The remaining $S$ = 5/2 spins exhibited paramagnetic behavior in the low-field regions. The numerical analysis confirmed that the observed quantum state is a many-body entangled state based on the dominant AF interactions and is strongly stabilized by coupling with spin-5/2. The stabilization of this quantum state can be attributed to a compensation effect similar to magnetic field-induced superconductivity, which serves as a strategy to control the stability of quantum spin states in magnetic fields.

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Hironori Yamaguchi, Tsuyoshi Okubo, Akira Matsuo, Takashi Kawakami, Yoshiki Iwasaki, Taiki Takahashi, Yuko Hosokoshi, Koichi Kindo. 2024-04-10. Quantum spin state stabilized by coupling with classical spins. https://doi.org/10.1103/physrevb.109.l100404

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