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arXiv · 2204.12485

Competing orders, the Wess-Zumino-Witten term, and spin liquids

Yen-Ta Huang·Dung-Hai Lee
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Abstract

In this paper, we demonstrate that in frustrated magnets when several conventional (i.e., symmetry-breaking) orders compete, and are "intertwined" by a Wess-Zumino-Witten (WZW) term, the possibility of spin liquid arises. The resulting spin liquid could have excitations which carry fractional spins and obey non-trivial self/mutual statistics. As a concrete example, we consider the case where the competing orders are the N\'{e}el and valence-bond solid (VBS) order on square lattice. Examining different scenarios of vortex condensation from the VBS side, we show that the intermediate phases, including spin liquids, between the N\'{e}el and VBS order always break certain symmetry. Remarkably, our starting theory, without fractionalized particles (partons) and guage field, predicts results agreeing with those derived from a parton theory. This suggests that the missing link between the Ginzberg-Landau-Wilson action of competing order and the physics of spin liquid is the WZW term.

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Yen-Ta Huang, Dung-Hai Lee. 2022-04-26. Competing orders, the Wess-Zumino-Witten term, and spin liquids. https://doi.org/10.1016/j.nuclphysb.2022.116043

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