Metallicity in the half-filled Holstein-Hubbard model

Abstract

We re-examine the Peierls insulator to Mott insulator transition scenario in the one-dimensional Holstein-Hubbard model where, at half-filling, electron-phonon and electron-electron interactions compete for establishing charge- and spin-density-wave states, respectively. By means of large-scale density-matrix renormalization group calculations we determine the spin, single-particle and two-particle excitation gaps and prove--in the course of a careful finite-size scaling analysis--recent claims for an intervening metallic phase in the weak-coupling regime. We show that for large phonon frequencies the metallic region is even more extended than previously expected, and subdivided into ordinary Luttinger liquid and bipolaronic liquid phases.

5 pages, 7 figures, revised (extended) version, accepted for publication in EPL

References in corpus (5)

• Efficient DMFT-simulation of the Holstein-Hubbard Model
• Phase diagram for the one-dimensional Hubbard-Holstein model: A density-matrix renormalization group study
• Phase diagram of the one dimensional Hubbard-Holstein Model at 1/2 and 1/4 filling
• Quantum lattice dynamical effects on the single-particle excitations in 1D Mott and Peierls insulators
• Luttinger liquid versus charge density wave behaviour in the one-dimensional spinless fermion Holstein model

Cited by in corpus (2)

• Insulating behavior with spin and charge order in the ionic Hubbard model
• Quantum phase transition in a 1D transport model with boson affected hopping: Luttinger liquid versus charge-density-wave behavior