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Lattice anisotropy as microscopic origin of static stripes in cuprates

B. Normand·A. P. Kampf
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Abstract

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 \ne t_y) and t-J (t_x \ne t_y, J_x \ne J_y) models. Symmetrical but inhomogeneous (``polaronic'') charge structures in the isotropic models are altered even by rather small anisotropies to one-dimensional, stripe-like features. We find two distinct types of stripe, namely uniformly filled, antiphase domain walls and non-uniform, 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.

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B. Normand, A. P. Kampf. 2001-02-12. Lattice anisotropy as microscopic origin of static stripes in cuprates. https://doi.org/10.1103/physrevb.64.024521

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