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arXiv · 2209.00010

Where is the Quantum Spin Nematic?

Shengtao Jiang·Judit Romhányi·Steven R. White·M. E. Zhitomirsky·A. L. Chernyshev
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Abstract

We provide strong evidence of the spin-nematic state in a paradigmatic ferro-antiferromagnetic $J_1$--$J_2$ model using analytical and density-matrix renormalization group methods. In zero field, the attraction of spin-flip pairs leads to a first-order transition and no nematic state, while pair-repulsion at larger $J_2$ stabilizes the nematic phase in a narrow region near the pair-condensation field. A devil's staircase of multi-pair condensates is conjectured for weak pair-attraction. A suppression of the spin-flip gap by many-body effects leads to an order-of-magnitude contraction of the nematic phase compared to na\"ive expectations. The proposed phase diagram should be broadly valid.

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Shengtao Jiang, Judit Romhányi, Steven R. White, M. E. Zhitomirsky, A. L. Chernyshev. 2022-08-31. Where is the Quantum Spin Nematic?. https://doi.org/10.1103/physrevlett.130.116701

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