Renormalization of the electron–phonon interaction in the Hubbard model

✍ Scribed by R. Citro; S. Cojocaru; M. Marinaro

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 165 KB
• Volume: 359-361
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2005.01.196

✦ Synopsis

We calculate the electron-phonon vertex in the two-dimensional Hubbard model by a strong coupling approach based on cumulant expansion. The role of the on-site Coulomb interaction on the coupling of the electrons to the Holstein phonons is investigated in different regions of the Brillouin zone. The results reveal the presence of a strong forward scattering and an effective increase of the vertex function at low temperatures above a certain critical U.

Comparison with other approaches is also discussed.