Existence of an intervening metallic phase at the transition region of the charge-density-wave phase and the spin-density-wave phase in the 1-D Hubbard-Holstein model
Abstract
The Holstein-Hubbard model is considered to study the competition between the electron-phonon interaction and the electron-electron interaction in a one-dimensional correlated Fermi systemat half-filling. First, a series of canonical transformations that incorporate phonon coherence and correlation effectsis performed and then the transformed Hamiltonian is averaged with respect to a zero-phonon state. The resulting effective electronic Hamiltonian is finally solved exactly by the Bethe-ansatz technique. It is shown that the present method suggests the existence of a wider intermediate metallic phase at the SDW-CDW crossover region than the one predicted by the simple variational method of Takada and Chatterjee. The presence of this metallic phase is indeed a favorable situation from the point of view of high temperature superconductivity.
- Publication:
-
Advances in Basic Science (ICABS 2019)
- Pub Date:
- August 2019
- DOI:
- 10.1063/1.5122474
- Bibcode:
- 2019AIPC.2142k0014M