Resonating bipolaron driven pseudogap phase

The spin as well as charge pseudogap features in the high Tc cuprate can be traced back to the dynamical properties on small clusters (consisting of Cu ions together with their ligand O ions environments) which make up the overall structure of these materials. These ligand complexes being deformable, causes the itinerant electrons on the Cu ions to enter into resonating bipolaron states via binary collision processes, similar to the Feshbach resonance in ultra-cold fermionic gases. We illustrate such resonant pairing on an isolated cluster and discuss how, upon coupling together such clusters, the local physics evolves into global macroscopic features, such as lattice mediated driven superconducting, respectively insulating, states of such resonating bipolarons.