SciPost Phys. 7, 074 (2019) ·
published 3 December 2019

· pdf
We present quantum dimer models in two dimensions which realize metallic
ground states with Z2 topological order. Our models are generalizations of a
dimer model introduced in [PNAS 112,95529557 (2015)] to provide an effective
description of unconventional metallic states in holedoped Mott insulators. We
construct exact ground state wave functions in a specific parameter regime and
show that the ground state realizes a fractionalized Fermi liquid. Due to the
presence of Z2 topological order the Luttinger count is modified and the volume
enclosed by the Fermi surface is proportional to the density of doped holes
away from half filling. We also comment on possible applications to magicangle
twisted bilayer graphene.