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arXiv · 0803.3538

Nested Cluster Algorithm for Frustrated Quantum Antiferromagnets

M. Nyfeler·F. -J. Jiang·F. Kämpfer·U. -J. Wiese
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Abstract

Simulations of frustrated quantum antiferromagnets suffer from a severe sign problem. We solve the ergodicity problem of the loop-cluster algorithm in a natural way and apply a powerful strategy to address the sign problem. For the spin 1/2 Heisenberg antiferromagnet on a kagome and on a frustrated square lattice, a nested cluster algorithm eliminates the sign problem for large systems. The method is applicable to general lattice geometries but limited to moderate temperatures.

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M. Nyfeler, F. -J. Jiang, F. Kämpfer, U. -J. Wiese. 2008-03-25. Nested Cluster Algorithm for Frustrated Quantum Antiferromagnets. https://doi.org/10.1103/physrevlett.100.247206

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