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arXiv · 1602.05969

SU(2)$_1$ chiral edge modes of a critical spin liquid

Didier Poilblanc·Norbert Schuch·Ian Affleck
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Abstract

Protected chiral edge modes are a well-known signature of topologically ordered phases like the Fractional Quantum Hall States. Recently, using the framework of projected entangled pair states (PEPS) on the square lattice, we constructed a family of chiral Resonating Valence Bond states with $\mathbb{Z}_2$ gauge symmetry. Here we revisit and analyze in full details the properties of the edge modes as given by their Entanglement Spectra on a cylinder. Surprisingly, we show that the latter can be well described by a chiral SU(2)$_1$ Conformal Field Theory (CFT), as for the $ν=1/2$ (bosonic) gapped Laughlin state, although our numerical data suggest a critical bulk compatible with an emergent $U(1)$ gauge symmetry. We propose that our family of PEPS may physically describe a boundary between a chiral topological phase and a trivial phase.

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Didier Poilblanc, Norbert Schuch, Ian Affleck. 2016-02-27. SU(2)$_1$ chiral edge modes of a critical spin liquid. https://doi.org/10.1103/physrevb.93.174414

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