Regensburg 2004 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

TT: Tiefe Temperaturen

TT 24: Postersitzung III: Korrelierte Elektronen, ”Orbital Physics”

TT 24.19: Poster

Wednesday, March 10, 2004, 14:30–19:00, Poster A

Quartic Oscillator: Diagonalization by Continuous Unitary Transformations — •Sébastien Dusuel und Götz S. Uhrig — Zülpicherstr. 77, D-50937 Köln, Germany

The method of Continuous Unitary Transformations (CUTs) has been applied successfully to various many-body Hamiltonians. We here consider a simple model, namely a single quartic oscillator. Our aim is two-fold: First, it can be used as a pedagogical and illustrative introduction to the CUTs. Second, thanks to its simplicity, the quartic oscillator allows to gain an intuition about the CUTs. Various generators of the transformations are tested and their efficiency is compared. Various high-order truncation schemes are equally analyzed. The results are also compared to results from the functional renormalization group.