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Possible Existence Of Topological Excitations In Quantum Spin Models In Low Dimensions

Ranjan Chaudhury·Samir K. Paul
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Abstract

The possibility of existence of topological excitations in the anisotropic quantum Heisenberg model in one and two spatial dimensions is studied using coherent state method. It is found that a part of the Wess-Zumino term contributes to the partition function, as a topological term for ferromagnets in the long wavelength limit in both one and two dimensions. In particular, the XY limit of the two-dimensional anisotropic ferromagnet is shown to retain the topological excitations, as expected from the quantum Kosterlitz-Thouless scenario.

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Ranjan Chaudhury, Samir K. Paul. 1999-01-21. Possible Existence Of Topological Excitations In Quantum Spin Models In Low Dimensions. https://doi.org/10.1103/physrevb.60.6234

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