Journal of Physics Condensed Matter
Enhanced d-wave pairing in the two-dimensional Hubbard model with periodically modulated hopping amplitudes
Shuhui Yang, Xingcan Liu, Weiqi Li, Jianqun Yang, Tao Ying, Xingji Li, Xiudong Sun
Abstract
Abstract 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 ˆ -direction, while in the y ˆ -direction the hopping amplitudes are modulated with period P, where t y = t + d t , t y ′ = t − ( P − 1 ) d t , 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.