A bilayer Double Semion Model with Symmetry-Enriched Topological Order

L. Ortiz; M. A. Martin-Delgado

doi:10.1016/j.aop.2016.10.008

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arXiv · 1604.08656

A bilayer Double Semion Model with Symmetry-Enriched Topological Order

L. Ortiz·M. A. Martin-Delgado

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Abstract

We construct a new model of two-dimensional quantum spin systems that combines intrinsic topo- logical orders and a global symmetry called flavour symmetry. It is referred as the bilayer Doubled Semion model (bDS) and is an instance of symmetry-enriched topological order. A honeycomb bi- layer lattice is introduced to combine a Double Semion Topolgical Order with a global spin-flavour symmetry to get the fractionalization of its quasiparticles. The bDS model exhibits non-trival braid- ing self-statistics of excitations and its dual model constitutes a Symmetry-Protected Topological Order with novel edge states. This dual model gives rise to a bilayer Non-Trivial Paramagnet that is invariant under the flavour symmetry and the well-known spin flip symmetry.

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L. Ortiz, M. A. Martin-Delgado. 2016-04-29. A bilayer Double Semion Model with Symmetry-Enriched Topological Order. https://doi.org/10.1016/j.aop.2016.10.008

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