Simplified parquet equations for the Anderson impurity model: comparison with numerically exact solutions

0482232 - FZÚ 2018 RIV PL eng J - Journal Article
Pokorný, Vladislav - Žonda, M. - Kauch, Anna - Janiš, Václav
Simplified parquet equations for the Anderson impurity model: comparison with numerically exact solutions.
Acta Physica Polonica A. Roč. 131, č. 4 (2017), s. 1042-1044. ISSN 0587-4246. E-ISSN 1898-794X
R&D Projects: GA ČR GA15-14259S
Institutional support: RVO:68378271
Keywords : Anderson model * parquet equations * numerical renormalization group
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 0.857, year: 2017

We use an analytic solver for the single-impurity Anderson model based on simplified parquet equations to describe the Kondo asymptotics. This scheme uses a two-particle self-consistency to control the strong-coupling Kondo critical behavior of this model at half filling. The equations can be written in the real-frequency representation, which gives us direct access to spectral functions unlike numerical schemes in the Matsubara formalism. We compare our results to those obtained by second-order perturbation theory, numerical renormalization group, and continuous-time quantum Monte Carlo in order to assess the reliability of this approximation.

Permanent Link: http://hdl.handle.net/11104/0277613