Symmetry-protected topological phases, generalized Laughlin argument, and orientifolds
Symmetry-protected topological phases, generalized Laughlin argument, and orientifolds
We generalize Laughlin's flux insertion argument, originally discussed in the context of the quantum Hall effect, to topological phases protected by non-on-site unitary symmetries, in particular by parity symmetry or parity symmetry combined with an on-site unitary symmetry. As a model, we discuss fermionic or bosonic systems in two spatial …