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arXiv · 1112.1100

Three-sublattice order in the SU(3) Heisenberg model on the square and triangular lattice

Bela Bauer·Philippe Corboz·Andreas M. Läuchli·Laura Messio·Karlo Penc·Matthias Troyer·Frédéric Mila
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Abstract

We present a numerical study of the SU(3) Heisenberg model of three-flavor fermions on the triangular and square lattice by means of the density-matrix renormalization group (DMRG) and infinite projected entangled-pair states (iPEPS). For the triangular lattice we confirm that the ground state has a three-sublattice order with a finite ordered moment which is compatible with the result from linear flavor wave theory (LFWT). The same type of order has recently been predicted also for the square lattice [PRL 105, 265301 (2010)] from LFWT and exact diagonalization. However, for this case the ordered moment cannot be computed based on LFWT due to divergent fluctuations. Our numerical study clearly supports this three-sublattice order, with an ordered moment of m=0.2-0.4 in the thermodynamic limit.

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Bela Bauer, Philippe Corboz, Andreas M. Läuchli, Laura Messio, Karlo Penc, Matthias Troyer, Frédéric Mila. 2012-03-21. Three-sublattice order in the SU(3) Heisenberg model on the square and triangular lattice. https://doi.org/10.1103/physrevb.85.125116

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