Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2006-12-11
Phys. Rev. B 75, 245103 (2007)
Physics
Condensed Matter
Strongly Correlated Electrons
10 pages, 10 eps figures
Scientific paper
10.1103/PhysRevB.75.245103
The Hubbard-Holstein model is one of the simplest to incorporate both electron-electron and electron-phonon interactions. In one dimension at half filling the Holstein electron-phonon coupling promotes onsite pairs of electrons and a Peierls charge density wave while the Hubbard onsite Coulomb repulsion U promotes antiferromagnetic correlations and a Mott insulating state. Recent numerical studies have found a possible third intermediate phase between Peierls and Mott states. From direct calculations of charge and spin susceptibilities, we show that (i) As the electron-phonon coupling is increased, first a spin gap opens, followed by the Peierls transition. Between these two transitions the metallic intermediate phase has a spin gap, no charge gap, and properties similar to the negative-U Hubbard model. (ii) The transitions between Mott/intermediate and intermediate/Peierls states are of the Kosterlitz-Thouless form. (iii) For larger U the two transitions merge at a tritical point into a single first order Mott/Peierls transition. In addition we show that an intermediate phase also occurs in the quarter-filled model.
Clay Torsten R.
Hardikar R. P.
No associations
LandOfFree
Phase diagram of the one dimensional Hubbard-Holstein Model at 1/2 and 1/4 filling does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Phase diagram of the one dimensional Hubbard-Holstein Model at 1/2 and 1/4 filling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase diagram of the one dimensional Hubbard-Holstein Model at 1/2 and 1/4 filling will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-117399