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arXiv · 0806.1713

Vortex-enhanced alternating order around impurities in antiferromagnets

Ruggero Vaia·Alessandro Cuccoli
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Abstract

It has been recently pointed out that the presence of a nonmagnetic impurity in a Heisenberg antiferromagnet generates an alternating order of the surrounding spins which is independent of temperature in a wide range. Quantum Monte Carlo simulations in the two-dimensional $S=1/2$ case confirmed this picture, but showed a counterintuitive enhancement of the alternating order around the Kosterlitz-Thouless transition. We propose here an explanation in terms of the effect of vortex excitations.

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Ruggero Vaia, Alessandro Cuccoli. 2008-06-10. Vortex-enhanced alternating order around impurities in antiferromagnets. https://arxiv.org/abs/0806.1713

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