Physical realization and possible identification of topological excitations in quantum Heisenberg ferromagnet on lattice

Ranjan Chaudhury; Samir K. Paul

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arXiv · cond-mat/0612211

Physical realization and possible identification of topological excitations in quantum Heisenberg ferromagnet on lattice

Ranjan Chaudhury·Samir K. Paul

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Abstract

Physical configurations corresponding to topological excitations present in the XY limit of a quantum spin 1/2 Heisenberg ferromagnet, are investigated on a two dimensional square lattice. Quantum vortices(anti-vortices) are constructed in terms of terms of coherent spin field components and the crucial role of the associated Wess-Zumino term is highlighted. It is shown that this term can identify a large class of vortices(anti-vortices). In particular the excitations with odd topological charge belonging to this class, are found to exhibit a self-similar pattern regarding the internal charge distribution. Our formalism is distinctly different from the coventional approach for the construction of quantum vortices(anti-vortices).

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Ranjan Chaudhury, Samir K. Paul. 2007-03-07. Physical realization and possible identification of topological excitations in quantum Heisenberg ferromagnet on lattice. https://arxiv.org/abs/cond-mat/0612211

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