Understanding superconductivity emerging from repulsive fermions remains a major challenge in condensed matter physics. In this paper, we investigate the pairing tendencies in a one-dimensional, three-component repulsive Hubbard model, using the density matrix renormalization group method. At half filling, the system exhibits density wave ground state due to strong Hubbard repulsions. Upon doping, Cooper pairs can emerge in the system, whose long-range fluctuations predominate the low-energy physics across a broad parameter range. The effective attractions between Cooper pairs are mediated by the particle-hole fluctuations in the third nonpairing component, resembling an excitoniclike mechanism of superconductivity. The coexistence of density waves and superconductivity at different fermion fillings is explored. We also present an analytical study of the pairing mechanism in both weak and strong coupling limits. Our results provide a new perspective for understanding and exploring unconventional superconductivities in strongly correlated fermionic systems.

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• Pairing mechanisms
• Superconductivity
• Strongly correlated systems
• Density matrix renormalization group
• Hubbard model
• Luttinger liquid model