Speaker
Didier Poilblanc
Description
Protected chiral edge modes are a well-known signature of
topologically ordered phases like the Fractional Quantum Hall
States (FQHS).
Using the framework of projected entangled pair states
(PEPS) on the square lattice, we construct a family of
chiral spin-1/2 quantum spin liquids with $\mathbb{Z}_2$
gauge symmetry and analyze in full details the properties of
the edge modes. Surprisingly,
we show that the latter can be well described by a chiral
Conformal Field Theory of free bosons (SU(2)$_1$), as for
the $\nu=1/2$ (bosonic) gapped
Laughlin state, despite the fact that our numerical data
suggest a critical bulk.
We propose that our family of PEPS physically describes a
boundary between a chiral topological phase and a trivial
phase
and might be closely connected to an (unknown) analogous
FQHS.
