Fig. 3: Unconventional superconductivity from IVC fluctuations.

a Complex pair wave-function of the gapped chiral superconductor showing magnitude (intensity) and phase (hue). Coulomb repulsion favors a sign change between the interior and exterior Fermi surfaces (dotted white lines). b Real pair wave-function of nodal non-chiral superconductor with 6-fold oscillations around the annular Fermi surfaces. c, d Schematic depiction of the favored superconducting pairings extended from momenta patches around \(K/{K}^{\prime}\) points (white boxes) to the entire hexagonal BZ (dotted white lines), for spin-singlets (left) and triplets (right). e T_c of the gapped chiral superconductor (e.g., d + id spin-singlet) within the self-consistent BCS calculations as a function of ξ_IVC. Calculations at density n_e = −1.7 × 10¹² cm⁻², u = 30 meV, including the effect of Coulomb repulsion with screening \({q}_{{{{{{{{\rm{TF}}}}}}}}}=\frac{{e}^{2}}{\epsilon }{\chi }_{0}\) and IVC fluctuations (Eq. (10)) of strength g = n_e/χ₀ ≈ 6 meV, where χ₀ is the DOS at the Fermi energy. f Electron-scattering between valleys by IVC fluctuations (indicated by blue arrows), showing how an attractive interaction in the IVC channel is converted to a repulsive interaction between inter-valley Cooper pairs. Only one Fermi surface in each valley is shown. The Fermi surfaces are enlarged relative to the BZ for clarity.