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arXiv · 1212.0863

Spin quantum Hall effects in a spin-1 topological paramagnet

Yuan-Ming Lu·Dung-Hai Lee
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Abstract

AKLT state (or Haldane phase) in a spin-1 chain represents a large class of gapped topological paramagnets, which hosts symmetry-protected gapless excitations on the boundary. In this work we show how to realize this type of featureless spin-1 states on a generic two-dimensional lattice. These states have a gapped spectrum in the bulk but supports gapless edge states protected by spin rotational symmetry along a certain direction, and are featured by spin quantum Hall effect. Using fermion representation of integer-spins we show a concrete example of such spin-1 topological paramagnets on kagome lattice, and suggest a microscopic spin-1 Hamiltonian which may realize it.

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Yuan-Ming Lu, Dung-Hai Lee. 2014-05-30. Spin quantum Hall effects in a spin-1 topological paramagnet. https://doi.org/10.1103/physrevb.89.184417

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