Enhanced d-wave pairing in the two-dimensional Hubbard model with periodically modulated hopping amplitudes

Utilizing determinant quantum Monte Carlo algorithm, the evolution of the d-wave pairing in the Hubbard model on the square lattice tuned by the periodically modulated hopping amplitudes is studied. The hopping amplitudes are homogeneous in the (x) over cap -direction, while in the (y) over cap -direction the hopping amplitudes are modulated with period P, where t(y) = t + dt, t(y)' = t - (P - 1)dt, and the modulation period P equals 2, 3 and 4 lattice spacings. The latter two modulation periods are motivated by the observation of period-3 and period-4 stripe order in cuprate superconductors. For all the periods P, we find that the modulated hopping inhomogeneity enhances the d-wave pairing and an optimal inhomogeneity exists.

Automated summary

By studying the effect of periodically modulated hopping amplitudes on the d-wave pairing in the Hubbard model on a square lattice, it is found that the modulation enhances the d-wave pairing and there exists an optimal inhomogeneity.