Fig. 5: Effect of local lattice distortions.
From: Competing electronic states emerging on polar surfaces
a Energy dependence of all electronic states on the lattice distortions; the ions are progressively moved (by using a linear interpolation, see Methods Section) from the FE-distorted 1 × 1 lattice (0%) to the structure distorted by bipolarons aligned along [110] (100%); a transient phase is observed, showing single-electron polarons coexisting with the CDW (with a local energy minimum around 50%). b Bipolaron splitting, i.e., transition from bipolarons aligned along [110] (0%) to a mixed configuration of bipolarons and surface and sub-surface polarons (100%), representing the most stable charge ordering pattern.
