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Derivation of the generalized Non Linear Sigma Model in the presence of the Dzyaloshinskii-Moriya interaction

L. Benfatto·M. Silva Neto·V. Juricic·C. Morais Smith
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Abstract

We derive the long-wavelength non-linear sigma model for a two-dimensional Heisenberg system in the presence of the Dzyaloshinskii-Moriya and pseudodipolar interactions. We show that the system is a non-conventional easy-axis antiferromagnet, displaying an anomalous coupling between the magnetic field and the staggered order parameter. Our results are in good agreement with recent experimental data for undoped La2CuO4 compounds.

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L. Benfatto, M. Silva Neto, V. Juricic, C. Morais Smith. 2005-12-21. Derivation of the generalized Non Linear Sigma Model in the presence of the Dzyaloshinskii-Moriya interaction. https://doi.org/10.1016/j.physb.2006.01.194

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