Electron-phonon coupling in the self-consistent Born approximation of the t-J model
| dc.creator | Gunnarsson, O. | |
| dc.creator | Rösch, O. | |
| dc.date | 2006-02-14 | |
| dc.date.accessioned | 2026-07-07T07:41:11Z | |
| dc.date.available | 2026-07-07T07:41:11Z | |
| dc.description | We study an undoped t-J model with electron-phonon interaction using the self-consistent Born approximation (SCBA). By neglecting vertex corrections, the SCBA solves a boson-holon model, where a holon couples to phonons and magnons. Comparison with exact diagonalization results for the t-J model suggests that the SCBA describes the electron-phonon interaction fairly accurately over a substantial range of J/t values. Exact diagonalization of the boson-holon model shows that the deviations are mainly due to the neglect of vertex corrections for small J/t and due to the replacement of the t-J model by the boson-holon model for large J/t. For typical values of J/t, the electron-phonon part Sigma_ep of the electron self-energy has comparable contributions from the second order diagram in the electron-phonon interaction and a phonon induced change of magnon diagrams. A very simple approximation to Sigma_ep gives a rather accurate effective mass. Using this approximation, we study the factors influencing the electron-phonon interaction. Typically, we find that the magnons nominally have a stronger coupling to the holon than the phonons. The phonons, nevertheless, drive the formation of small polarons (self-localization) due to important differences between the character of the phonon and magnon couplings. | |
| dc.description | 7 pages, RevTeX, 6 eps figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0602327 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0602327 | |
| dc.identifier | Phys. Rev. B 73, 174521 (2006) | |
| dc.identifier | doi:10.1103/PhysRevB.73.174521 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/122012 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.subject | Materials Science | |
| dc.title | Electron-phonon coupling in the self-consistent Born approximation of the t-J model | |
| dc.type | text |