Non-abelian bosonization of fermion symmetry-protected topological states

Yen-Ta Huang; Dung-Hai Lee

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arXiv · 2206.09393

Non-abelian bosonization of fermion symmetry-protected topological states

Yen-Ta Huang·Dung-Hai Lee

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Abstract

Applying the results of Ref.[1], we carry out the non-abelian bosonization for a class of free fermion symmetry-protected topological states (SPTs). The resulting boson theories are non-linear sigma models with topological $\theta$ term, thus unifying the field theory description of the (free) fermionic and bosonic SPTs. Tuning $\theta$ from $0$ to $2\pi$ triggers the topological trivial to non-trivial phase transitions. In addition, applying the same idea to the symmetry-protected critical spin liquids, we obtain the NL$\s$ models for spin SPTs living in one spatial dimension higher.

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Yen-Ta Huang, Dung-Hai Lee. 2022-06-19. Non-abelian bosonization of fermion symmetry-protected topological states. https://arxiv.org/abs/2206.09393

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