Time-reversal invariant topological gapped phases in bilayer Dirac materials

Abstract

We show that a plethora of topological insulating phases can appear in bilayer Dirac materials, including first-order topological insulators, topological mirror insulators, and second-order topological insulators. By considering doping and short-range attractive interactions, we show at a mean-field level that intrinsic odd-parity superconductivity can arise in such systems. Depending on the number and positions of Fermi surfaces in the normal state, we find that the resulting odd-parity superconductivity can lead to diverse time-reversal invariant topological superconducting phases, including topological superconductors and topological mirror superconductors. Our findings suggest that bilayer Dirac materials could be an excellent platform for investigating topological phases.