ArXiv · 2026
At weak coupling, finite-momentum superconductivity is typically associated with broken time-reversal or inversion symmetry of the Fermi surface. Here, we show that lattice-scale pair-density-wave order in rhombohedral multilayer graphene can arise from layer/orbital-dependent pairing interactions, band chirality, and Dirac-point-centered Fermi surface topology while preserving both symmetries. Using mean-field theory and comparing finite momentum sectors Q = ± 2 K_D with the Q = 0 superconducting state, we find that layer-dependent interactions of opposite signs (V_1A=-V_JB=-|V|) favor an intra-valley Kekulè state with center-of-mass momentum ( Q=± 2 K_D). In the presence of a time-reversal and inversion symmetry-preserving Kane-Mele mass (λ), this state appears only above a critical carrier density (nᶜʳⁱᵗ_K(λ,J)). The two superconducting condensates exhibit opposite chirality, J(-J) for K_D(-K_D) valleys, thereby preserving time-reversal and inversion symmetry. We map the phase diagram and analyze the dependence of T_c on the chirality index J and λ. We also evaluate the superfluid stiffness in the Kekulè superconducting state, thereby determining the Berezinskii-Kosterlitz-Thouless (BKT) transition temperature. Our results show that orbital-dependent interactions in the presence of band chirality favor finite-momentum pairing in time-reversal and inversion symmetric Dirac materials.
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