SCBA within composite operator method for the Hubbard model

✍ Scribed by S. Krivenko; A. Avella; F. Mancini; N. Plakida

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 202 KB
• Volume: 359-361
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2005.01.186

✦ Synopsis

We study the self-energy corrections to a 2-pole projection scheme for the Hubbard model by means of the self-consistent Born approximation, truncated to the first order, within the composite operator method. The bosonic Green's functions (spin and charge propagators), appearing in the mode-coupling decomposition, are computed by means of a 2-pole expansion in full self-consistency with the zero-order 2-pole fermionic propagator. The effects of spin fluctuations on the band structure are analyzed and discussed in relation to numerical simulation results.