Lattice anisotropy as the microscopic origin of static stripes in cuprates

Structural distortions in cuprate materials offer a microscopic origin for anisotropies in electron transport in the basal plane. Using a real-space Hartree-Fock approach, we consider the ground states of the anisotropic Hubbard (t(x) not equal t(y)) and t-J (t(x)not equalt(y),J(x)not equalJ(y)) models. Symmetrical but inhomogeneous ("polaronic") charge structures in the isotropic models are altered even by rather small anisotropies to one-dimensional, stripelike features. We find two distinct types of stripe, namely uniformly filled, antiphase domain walls, and nonuniform, half-filled, in-phase ones. We characterize their properties, energies, and dependence on the model parameters, including filling and anisotropy in t (and J). We discuss the connections among these results, other theoretical studies, and experimental observation.