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Néel and Spin-Peierls ground states of two-dimensional SU(N) quantum antiferromagnets

Kenji Harada·Naoki Kawashima·Matthias Troyer
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Abstract

The two-dimensional SU(N) quantum antiferromagnet, a generalization of the quantum Heisenberg model, is investigated by quantum Monte Carlo simulations. The ground state for $N\le 4$ is found to be of the Néel type with broken SU(N) symmetry, whereas it is of the Spin-Peierls type for $N\ge 5$ with broken lattice translational invariance. No intermediate spin-liquid phase was observed in contrast to previous numerical simulations on smaller lattices [Santoro et al., Phys. Rev. Lett. {\bf 83} 3065 (1999)].

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Kenji Harada, Naoki Kawashima, Matthias Troyer. 2002-10-03. Néel and Spin-Peierls ground states of two-dimensional SU(N) quantum antiferromagnets. https://doi.org/10.1103/physrevlett.90.117203

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