Full Self-Consistent Projection Operator Approach to Nonlocal Excitations in Solids
- Title
- Full Self-Consistent Projection Operator Approach to Nonlocal Excitations in Solids
- Authors
- Kakehashi, Y; Nakamura, T; Fulde, P; null
- Date Issued
- 2009-12
- Publisher
- PHYSICAL SOC JAPAN
- Abstract
- A self-consistent projection operator method for single-particle excitations is developed. It describes the nonlocal correlations on the basis of a projection technique to the retarded Green function and the off-diagonal effective medium. The theory takes into account long-range intersite correlations making use of an incremental cluster expansion in the medium. A generalized self-consistent coherent potential is derived. It yields the momentum-dependent excitation spectra with high resolution. Numerical studies for the Hubbard model on a simple Cubic lattice at half filling show that the theory is applicable in a wide range of Coulomb interaction strength. In particular, it is found that the long-range antiferromagnetic correlations in the strong interaction regime cause shadow bands in the low-energy region and sub-peaks of the Mott-Hubbard bands.
- Keywords
- non-local excitations; momentum-dependent self-energy; Hubbard model; ARPES; COHERENT-POTENTIAL APPROXIMATION; HIGH-TEMPERATURE SUPERCONDUCTORS; MONTE-CARLO APPROACH; NARROW ENERGY BANDS; HUBBARD-MODEL; INFINITE DIMENSIONS; ELECTRON CORRELATIONS; VALENCE-BAND; METALLIC MAGNETISM; TRANSITION-METALS
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/27630
- DOI
- 10.1143/JPSJ.78.124710
- ISSN
- 0031-9015
- Article Type
- Article
- Files in This Item:
- There are no files associated with this item.
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