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Susceptibility of the 2D S=1/2 Heisenberg antiferromagnet with an impurity

Kaj H. Hoglund·Anders W. Sandvik
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Abstract

We use a quantum Monte Carlo method (stochastic series expansion) to study the effects of a magnetic or nonmagnetic impurity on the magnetic susceptibility of the two-dimensional Heisenberg antiferromagnet. At low temperatures, we find a log-divergent contribution to the transverse susceptibility. We also introduce an effective few-spin model that can quantitatively capture the differences between magnetic and nonmagnetic impurities at high and intermediate temperatures.

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Kaj H. Hoglund, Anders W. Sandvik. 2003-09-01. Susceptibility of the 2D S=1/2 Heisenberg antiferromagnet with an impurity. https://doi.org/10.1103/physrevlett.91.077204

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