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Spin Dynamics in the Two-Dimensional Spin 1/2 Heisenberg Antiferromagnet

A. F. Albuquerque·A. S. T. Pires·M. E. Gouvea
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Abstract

We present low-temperature dynamic properties of the quantum two-dimensional antiferromagnetic Heisenberg model with spin S=1/2. The calculation of the dynamic correlation function is performed by combining a projection operator formalism and the modified spin-wave theory (MSW), which gives a gap in the dispersion relation for finite temperatures. The so calculated dynamic correlation function shows a double peak structure.We also obtain the spin-wave damping and compare our results to experimental data and to theoretical results obtained by other authors using different approaches.

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A. F. Albuquerque, A. S. T. Pires, M. E. Gouvea. 2005-05-18. Spin Dynamics in the Two-Dimensional Spin 1/2 Heisenberg Antiferromagnet. https://doi.org/10.1103/physrevb.72.174423

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