We present a quantum-number projection technique which enables us to exactly treat spin, momentum, and other symmetries embedded in the Hubbard model. By combining this projection technique, we extend the path-integral renormalization-group method to improve the efficiency of numerical computations. By taking numerical calculations for the standard Hubbard model and the Hubbard model with next-nearest-neighbor transfer, we show that the present extended method can extremely enhance numerical accuracy and that it can handle excited states, in addition to the ground state.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2004 Mar 23|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics