Fractional Chern insulator induced by scalar-spin-chirality on a kagome lattice

The fractional Chern insulator (FCI) is the lattice analog of the fractional quantum Hall state. In this work, we demonstrate the emergence of the FCI in a spin-anisotropic ordered system on a kagome lattice [1]. When constructing an effective Hamiltonian within the lowest Chern band subspace, we include a repulsive electron-electron interaction [2] along with the effect of the band dispersion. To determine whether the emergent ground states correspond to the FCI, we examine (i) the overlap with a representative FCI state, (ii) the ground state degeneracy, and (iii) the remaining energy gap in the thermodynamic limit [3].