Superconductivity in the doped Hubbard model and its interplay with next-nearest hopping t ′

“…2a-c. Consistent with previous reports on CaCuO 2 17,18 , a large zone boundary dispersion E ZB = _ωð 1 2 ,0Þ À _ωð 1 4 , 1 4 Þ of the single magnon excitation is observed with an essentially non-dispersive section along the (h, h) direction. Away from the Brillouin zone center, the bimagnon dispersion ℏω bm roughly mimics the single magnon dispersion ℏω sm .…”

“…The second one follows from the suggested crucial role played by the longer-range hoppings in the t-J models. Such a result goes in line with, inter alia, recent works advocating for the strong sensitivity of the phase diagram of the t-J like models to the value of the next-nearest neighbor hopping t [53,54] and thus 'sweetens the bad news' coming from the study suggesting the lack of superconductivity in the ground state of the 2D Hubbard model without longer-range hoppings [55]. The third point relates to the fact that, as stated above, solely the short-range magnetic correlations are needed to explain the persistence of the intensity of the paramagnons in doped cuprates, similar to the recently established well-defined magnons in the random t-J model up to 33% hole doping [56].…”

“…It is clear that F (r) also decays exponentially as F (r) ∝ e −r/ξs , where the extracted correlation length ξ s ≈ 10 lattice spacings. This is also similar with previous study of the single-band Hubbard model on the square lattice [33].…”