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Coexistence of non-Abelian chiral spin liquid and magnetic order in a spin-1 antiferromagnet

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 نشر من قبل Yixuan Huang
 تاريخ النشر 2021
  مجال البحث فيزياء
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We study the ground-state properties of a spin-1 Heisenberg model on the square lattice with the first and second nearest-neighbor antiferromagnetic couplings $J_1$, $J_2$ and a three-spin scalar chirality term $J_chi$. Using the density matrix renormalization group calculation, we map out a global phase diagram including various magnetic order phases and an emergent quantum spin liquid phase. The nature of the spin liquid is identified as a bosonic non-Abelian Moore-Read state by the fingerprint of the entanglement spectra and identification of a full set of topological sectors. We further unveil a stripe magnetic order coexisting with this spin liquid. Our results not only establish a rare example of non-Abelian spin liquids in simple spin systems, but also demonstrate the coexistence of fractionalized excitations and magnetic order beyond mean-field descriptions.

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