Abstract
A strong-coupling expansion for models of correlated electrons in any dimension is presented. The method is applied to the Hubbard model in dimensions and compared with numerical results in . Third order expansion of the Green's function suffices to exhibit both the Mott metal-insulator transition and a low-temperature regime where antiferromagnetic correlations are strong. It is predicted that some of the weak photoemission signals observed in one-dimensional systems such as should become stronger as temperature increases away from the spin-charge separated state.
- Received 23 October 1997
DOI:https://doi.org/10.1103/PhysRevLett.80.5389
©1998 American Physical Society