Abstract
We demonstrate for the nearly half-filled Holstein-Hubbard model that the presence of antiferomagnetic spin correlations can cause polaronic carrier self-localization, and hence a strongly anharmonic lattice potential, already at moderate electron-phonon coupling strengths λ∼0.2–0.4, up to substantial hole dopant concentrations ∼(20–30)%. The results are compared to recent observations of anharmonicity in the apical oxygen c-axis motion of cuprate superconductors.
- Received 19 December 1991
DOI:https://doi.org/10.1103/PhysRevLett.69.1600
©1992 American Physical Society
