Three-dimensional time-reversal invariant topological superconductivity in doped chiral topological semimetals

Chiral topological semimetals host multifold degenerate band crossing points under the protection of crystalline symmetries. In this paper, we suggest the recently discovered chiral topological semimetals in space group P2₁3 (No. 198), parts of which are superconducting upon doping, can be new candidates of time-reversal-invariant topological superconductors. By investigating the Fermi surfaces around the band crossing points, we clarify how the nontrivial topology of chiral topological semimetals affects their superconducting state and show the existence of topological superconductivity with surface Majorana fermions. We further demonstrate that the topological superconductivity is favored by inter-unit cell phonon-mediated electron-electron interaction.