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arXiv · 2411.09542

Spin Liquid Landscapes in the Kagome Lattice: A Variational Monte Carlo Study of the Chiral Heisenberg Model and Experimental Signatures

Abstract

Chiral spin liquids, which break time-reversal symmetry, are of great interest due to their topological properties and fractionalized excitations (anyons). In this work, we investigate chiral spin liquids (CSL) on the kagome lattice arising from the competition between the third-nearest-neighbor Heisenberg interaction across hexagons ($J_d$) and a staggered scalar spin chirality term ($J_χ$). Using variational Monte Carlo methods, we map out the phase diagram and identify various gapped and gapless CSL phases, each characterized by a distinct flux pattern. Notably, the interplay between $J_d$ and $J_χ$ induces a tricritical point, which we analyze using Landau-Ginzburg theory. Additionally, we identify potential signatures of these CSLs-including distinctive spin-spin correlations, anomalies in the static spin structure factor, longitudinal thermal conductivity, and magentoelectric effects-which offer practical guidance for their future experimental detection.

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Hee Seung Kim, Hyeok-Jun Yang, Karlo Penc, SungBin Lee. 2026-01-16. Spin Liquid Landscapes in the Kagome Lattice: A Variational Monte Carlo Study of the Chiral Heisenberg Model and Experimental Signatures. https://arxiv.org/abs/2411.09542

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