Correlated squeezed polaron states in one dimension
- 1 October 1993
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 48 (14), 10183-10187
- https://doi.org/10.1103/physrevb.48.10183
Abstract
In this paper we have applied the correlated squeezed-state approach to investigate the ground-state properties of the one-dimensional Hubbard model with a local Holstein-type electron-phonon interaction. We have introduced a variational ground state in which the phonon subsystem is in a correlated squeezed state. The correlated squeezed state has built in the correlation between different phonon modes induced by the linear coupling with the electrons. With optimal values of the variational parameters the correlated squeezed state will by construction yield an energy lower than those obtained in earlier treatments. This means that our variational ansatz is more stable as the ground state of the system. Furthermore, our variational study shows that in the correlated squeezed state the polaronic reduction effect of phonons is much more alleviated, and thus the mass enhancement inherent to the polaron effect is considerably weakened. This weakening of the reduction effect should, in turn, affect other physical properties of the system.Keywords
This publication has 12 references indexed in Scilit:
- Correlated squeezed phonon statesPhysics Letters A, 1992
- Correlated-squeezed-state approach for phonon coupling in a tunneling systemPhysical Review B, 1991
- Variational study of the linear Jahn-Teller effect: Case of an electronic doublet interacting with a doubly degenerate vibrationPhysical Review A, 1991
- Variational treatment of the strong electron-phonon interactionJournal of Physics: Condensed Matter, 1989
- Variational ground state of a system with strong electron-phonon interactionPhysical Review B, 1988
- Squeezed polarons in one dimensionPhysics Letters A, 1988
- New type of Cooper pairing in systems with strong electron-phonon interactionPhysical Review B, 1988
- Reconsideration of a simple model for bipolaronsSolid State Communications, 1988
- Squeezed LightJournal of Modern Optics, 1987
- Studies of polaron motion: Part I. The molecular-crystal modelAnnals of Physics, 1959