Functional Renormalization Group Approach for Inhomogeneous Interacting Fermi-Systems
Abstract
The functional renormalization group approach has the property that, in general, the flow equation for the two-particle vertex generates (N4) independent variables, where N is the number of interacting states (e.g. sites of a real-space discretization). In order to include the flow equation for the two-particle vertex one needs to make further approximations if N becomes too large. In this talk we present such an approximation scheme, called the coupled-ladder approximation, for the special case of onsite interaction. Like the generic third-order-truncated fRG, the coupled-ladder approximation is exact to second order and is closely related to a simultaneous treatment of the Random Phase Approximation in all channels, i.e. summing up parquet-type diagrams.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2014
- Bibcode:
- 2014APS..MARG54010B