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arXiv · 1702.01359

Quantum spin liquid with 7 elementary particles

Haoyu Wang·Hitesh J. Changlani·Yuan Wan·Oleg Tchernyshyov
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Abstract

We present an exactly solvable model of a quantum spin liquid with Abelian anyons in d=2 spatial dimensions. With spins 1/2 on a triangular lattice and six-body interactions, our model has zero spin correlation length and localized elementary excitations like the toric codes of Kitaev and Wen. In contrast to those earlier models, it has more elementary particles---4 bosons and 3 fermions---and higher topological degeneracy of 64 on a torus. Elementary excitations are boson-fermion pairs that come in 12 distinct flavors. We use string operators to expose the topological nature of the model.

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Haoyu Wang, Hitesh J. Changlani, Yuan Wan, Oleg Tchernyshyov. 2017-03-30. Quantum spin liquid with 7 elementary particles. https://doi.org/10.1103/physrevb.95.144425

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