Motivated by the important role of next-nearest-neighbor hopping $t^{\prime }$ in the Hubbard model, we perform a systematic quantum Monte Carlo study of the superconducting pairing correlation in the heavily doped Hubbard model. By combining the determinant quantum Monte Carlo with constrained-path quantum Monte Carlo simulations, we discover that the dominant $d_{xy}$-wave pairing symmetry is sharply enhanced by positive $t^{\prime }$ both at finite and zero temperatures, highlighting the critical role of $t^{\prime }$ in manipulating superconducting pairing symmetry. Accompanied by the occurrence of $d_{xy}$-wave pairing symmetry, the antiferromagnetic fluctuations disappear but the spiral magnetic order can be enhanced by increasing $U$ or $t^{\prime }$. Moreover, when the pairing correlation of $d_{xy}$-wave pairing symmetry is sharply increased by $t^{\prime }$, the sign problem also shows a sharp decrease, indicating an interesting relationship between superconductivity and the sign problem. Generally, our unbiased simulations provide an important insight into the superconducting pairing mechanism in the heavily doped Hubbard model and also might offer useful information to understand the superconducting pairing symmetry of unconventional superconductors.

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• Strongly correlated systems
• Superconductivity
• Hubbard model
• Quantum Monte Carlo