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arXiv · 0808.0520

Phase Transition in Heisenberg Stacked Triangular Antiferromagnets: End of a Controversy

V. Thanh Ngo·H. T. Diep
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Abstract

By using the Wang-Landau flat-histogram Monte Carlo (MC) method for very large lattice sizes never simulated before, we show that the phase transition in the frustrated Heisenberg stacked triangular antiferromagnet is of first-order, contrary to results of earlier MC simulations using old-fashioned methods. Our result lends support to the conclusion of a nonperturbative renormalization group performed on an effective Hamiltonian. It puts an end to a 20-year long controversial issue.

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V. Thanh Ngo, H. T. Diep. 2008-08-04. Phase Transition in Heisenberg Stacked Triangular Antiferromagnets: End of a Controversy. https://arxiv.org/abs/0808.0520

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