The two-dimensional bond-diluted quantum Heisenberg model at the classical percolation threshold

Anders W. Sandvik

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arXiv · cond-mat/9909230

The two-dimensional bond-diluted quantum Heisenberg model at the classical percolation threshold

Anders W. Sandvik

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Abstract

The two-dimensional antiferromagnetic S=1/2 Heisenberg model with random bond dilution is studied using quantum Monte Carlo simulation at the percolation threshold (50% of the bonds removed). Finite-size scaling of the staggered structure factor averaged over the largest connected clusters of sites on L*L lattices shows that long-range order exists within the percolating fractal clusters in the thermodynamic limit. This implies that the order-disorder transition driven by bond-dilution occurs exactly at the percolation threshold and that the exponents are classical. This result should apply also to the site-diluted system.

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Anders W. Sandvik. 1999-09-15. The two-dimensional bond-diluted quantum Heisenberg model at the classical percolation threshold. https://arxiv.org/abs/cond-mat/9909230

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