Strong Coupling Limit of the Holstein-Hubbard Model
Zhaoyu Han, Steven A. Kivelson, Hong Yao
Abstract
We analyze the quantum phase diagram of the Holstein-Hubbard model using an asymptotically exact strong coupling expansion. We find all sorts of interesting phases including a pair-density wave, a charge 4e (and even a charge 6e) superconductor, regimes of phase separation, and a variety of distinct charge-density-wave, spin-density-wave, and superconducting regimes. We chart the crossovers that occur as a function of the degree of retardation, i.e., the ratio of characteristic phonon frequency to the strength of interactions.
Topics & Concepts
PhysicsCharge density waveHubbard modelPhase diagramSuperconductivityCharge (physics)Coupling (piping)Condensed matter physicsLimit (mathematics)Phase (matter)Spin (aerodynamics)Wave functionQuantumQuantum mechanicsQuantum electrodynamicsMaterials scienceMetallurgyMathematical analysisMathematicsThermodynamicsPhysics of Superconductivity and MagnetismCold Atom Physics and Bose-Einstein CondensatesElectronic and Structural Properties of Oxides