Spontaneous fractional Chern insulators in transition metal dichalcogenide moiré superlattices

  title={Spontaneous fractional Chern insulators in transition metal dichalcogenide moir{\'e} superlattices},
  author={Heqiu Li and Umesh Kumar and Kai Sun and Shizeng Lin},
  journal={Physical Review Research},
Moiré superlattice realized in two-dimensional heterostructures offers an exciting platform to access stronglycorrelated electronic states. In this work, we study transition metal dichalcogenides (TMD) Moiré superlattices with time-reversal symmetry and nontrivial spin/valley-Chern numbers. Utilizing realistic material parameters and the method of exact diagonalization, we find that at certain twisting angle and fractional filling, gapped fractional topological states, i.e., fractional Chern… 

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