Multi-critical point in a diluted bilayer Heisenberg quantum antiferromagnet

Anders W. Sandvik

doi:10.1103/physrevlett.89.177201

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Multi-critical point in a diluted bilayer Heisenberg quantum antiferromagnet

Anders W. Sandvik

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Abstract

The S=1/2 Heisenberg bilayer antiferromagnet with randomly removed inter-layer dimers is studied using quantum Monte Carlo simulations. A zero-temperature multi-critical point (p*,g*) at the classical percolation density p=p* and inter-layer coupling g* approximately 0.16 is demonstrated. The quantum critical exponents of the percolating cluster are determined using finite-size scaling. It is argued that the associated finite-temperature quantum critical regime extends to zero inter-layer coupling and could be relevant for antiferromagnetic cuprates doped with non-magnetic impurities.

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Anders W. Sandvik. 2002-08-21. Multi-critical point in a diluted bilayer Heisenberg quantum antiferromagnet. https://doi.org/10.1103/physrevlett.89.177201

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