Berlin 2015 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 112: Correlated Electrons: (General) Theory 3

TT 112.5: Talk

Friday, March 20, 2015, 10:30–10:45, H 3010

Separability of dynamical and non-local correlations in three dimensions — Thomas Schäfer, Alessandro Toschi, and •Jan Martin Tomczak — Institute of Solid State Physics, Vienna University of Technology, A-1040 Vienna, Austria

While second-order phase transitions always cause strong non-local fluctuations, their effect on spectral properties crucially depends on the dimensionality.

For the important case of three dimensions, we show that the electron self-energy is well separable into a local dynamical part and static non-local contributions. In particular, our non-perturbative many-body calculations for the 3D Hubbard model at different fillings demonstrate that the quasi-particle weight remains essentially momentum-independent, also in the presence of overall large non-local corrections to the self-energy.

Relying on this insight we propose a "space-time-separated" scheme for many-body perturbation theory that is up to ten times more efficient than current implementations. Besides these far-reaching implications for state-of-the-art electronic structure schemes, our analysis may also provide guidance to the quest of going beyond them.

[1] arXiv:1411.5686