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arXiv · 1406.4767

Trimerized ground state of the spin-1 Heisenberg antiferromagnet on the kagome lattice

Hitesh J. Changlani·Andreas M. Läuchli
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Abstract

We study the phase diagram of the spin-1 quantum bilinear-biquadratic antiferromagnet on the kagome lattice using exact diagonalization and the density matrix renormalization group algorithm. The SU(3)-symmetric point of this model Hamiltonian is a spontaneously trimerized state whose qualitative nature persists even at the Heisenberg point, a finding that contrasts previous proposals. We report the ground state energy per site of the Heisenberg model to be -1.410(2) and establish the presence of a spin gap.

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Hitesh J. Changlani, Andreas M. Läuchli. 2016-01-28. Trimerized ground state of the spin-1 Heisenberg antiferromagnet on the kagome lattice. https://doi.org/10.1103/physrevb.91.100407

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