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Topological spin excitations of Heisenberg antiferromagnets in two dimensions

Tai-Kai Ng
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Abstract

In this paper we discuss the construction and the dynamics of vortex-like topological spin excitations in the Schwinger-boson description of Heisenberg antiferromagnets in two dimensions. The topological spin excitations are Dirac fermions (with gap) when spin value $S$ is a half-integer. Experimental and theoretical implications of these excitations are being investigated.

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Tai-Kai Ng. 1999-05-10. Topological spin excitations of Heisenberg antiferromagnets in two dimensions. https://doi.org/10.1103/physrevlett.82.3504

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