Abstract
Momentum and doping dependence of the static charge susceptibility in the model is investigated. Correlations lead to a strongly momentum-dependent renormalization of . The charge susceptibility near the region of the Brillouin zone is strongly suppressed as the hole density is decreased. However, contrary to naive expectations, around and remains large and practically unchanged at . This effect is consistent with a tendency towards low-energy charge fluctuations with the wave vectors along the direction, reported in earlier studies. Our main finding is that the above trends are amplified by -driven pairing effects, indicating that the pseudogap formation may promote the charge inhomogeneity. The next-nearest hopping leads to weakening of the above momentum-selective renormalizations of . We analyze the effects of long-range Coulomb interaction, taking into account a layered structure of cuprates. As an application, the results are discussed in the context of bond-stretching phonon softening in hole-doped cuprates. In particular, a peculiar doping and momentum dependence of the electron-phonon coupling constant is found.
4 More- Received 7 March 2006
DOI:https://doi.org/10.1103/PhysRevB.74.045124
©2006 American Physical Society