Particle-hole fluctuations and possible superconductivity in doped α-RuCl₃

We study various particle-hole excitations and possible superconducting pairings mediated by these fluctuations in doped α-RuCl₃ by using multi-band Hubbard model with all t_2g orbitals. By performing a random-phase-approximation (RPA) analysis, we find that among all particle-hole excitations, the j_eff=1/2 pseudospin fluctuations are dominant, suggesting the robustness of j_eff=1/2 picture even in the doped systems. We also find that the most favorable superconducting state has a d-wave pairing symmetry.