Quantum Monte Carlo study of the Hubbard model with next-nearest-neighbor hopping t′: pairing and magnetism

Using the finite-temperature determinant quantum Monte Carlo (DQMC) algorithm, we study the pairing symmetries of the Hubbard Hamiltonian with next-nearest-neighbor (NNN) hopping t ' on square lattices. By varying the value of t ', we find that the d-wave pairing is suppressed by the onset of t ', while the p + ip-wave pairing tends to emerge for low electron density and t ' around -0.7. Together with the calculation of the anti-ferromagnetic and ferromagnetic spin correlation function, we explore the relationship between anti-ferromagnetic order and the d-wave pairing symmetry, and the relationship between ferromagnetic order and the p + ip-wave pairing symmetry. Our results may be useful for the exploration of the mechanism of the electron pairing symmetries, and for the realization of the exotic p + ip-wave superconductivity.

Automated summary

Using the DQMC algorithm, we studied the pairing symmetries of the Hubbard Hamiltonian on square lattices with next-nearest-neighbor hopping t'. We found that d-wave pairing is suppressed by t' while p + ip-wave pairing tends to emerge for low electron density and specific values of t'. By calculating spin correlation functions, we explored the connections between anti-ferromagnetic/ferromagnetic orders and different pairing symmetries.