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arXiv · 2407.20629

Variational Monte Carlo Study of the 1/9 Magnetization Plateau in Kagome Antiferromagnets

Li-Wei He·Shun-Li Yu·Jian-Xin Li
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Abstract

Motivated by very recent experimental observations of the 1/9 magnetization plateaus in YCu$_3$(OH)$_{6+x}$Br$_{3-x}$ and YCu$_3$(OD)$_{6+x}$Br$_{3-x}$, our study delves into the magnetic field-induced phase transitions in the nearest-neighbor antiferromagnetic Heisenberg model on the kagome lattice using the variational Monte Carlo technique. We uncover a phase transition from a zero-field Dirac spin liquid to a field-induced magnetically disordered phase that exhibits the 1/9 magnetization plateau. Through a comprehensive analysis encompassing the magnetization distribution, spin correlations, chiral order parameter, topological entanglement entropy, ground-state degeneracy, Chern number and excitation spectrum, we pinpoint the phase associated with this magnetization plateau as a chiral $\mathbb{Z}_3$ topological quantum spin liquid and elucidate its diverse physical properties.

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Li-Wei He, Shun-Li Yu, Jian-Xin Li. 2024-07-30. Variational Monte Carlo Study of the 1/9 Magnetization Plateau in Kagome Antiferromagnets. https://doi.org/10.1103/physrevlett.133.096501

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