Identifying non-Abelian topological ordered state and transition by momentum polarization

Abstract

Using a method called momentum polarization, we study the quasiparticle topological spin and edge-state chiral central charge of non-Abelian topological ordered states described by Gutzwiller-projected wave functions. Our results verify that the fractional Chern insulator state obtained by Gutzwiller projection of two partons in bands of Chern number 2 is described by $SU(2)_2$ Chern-Simons theory coupled to fermions, rather than the pure $SU(2)_2$ Chern-Simons theory. In addition, by introducing an adiabatic deformation between one Chern number 2 band and two Chern number 1 bands, we show that the topological order in the Gutzwiller-projected state does not always agree with the expectation of topological field theory. Even if the parton mean-field state is adiabatically deformed, the Gutzwiller projection can introduce a topological phase transition between Abelian and non-Abelian topologically ordered states. Our approach applies to more general topologically ordered states described by Gutzwiller-projected wave functions.