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Vortices in Quantum Spin Systems

John Schliemann·Franz G. Mertens
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Abstract

We examine spin vortices in ferromagnetic quantum Heisenberg models with planar anisotropy on two-dimensional lattices. The symmetry properties and the time evolution of vortices built up from spin-coherent states are studied in detail. Although these states show a dispersion typical for wave packets, important features of classical vortices are conserved. Moreover, the results on symmetry properties provide a construction scheme for vortex-like excitations from exact eigenstates, which have a well-controlled time evolution. Our approach works for arbitrary spin length both on triangular and square lattices.

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John Schliemann, Franz G. Mertens. 1998-11-20. Vortices in Quantum Spin Systems. https://arxiv.org/abs/cond-mat/9809401

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