Functional renormalization group for a large moiré unit cell

A NUMERICAL RENORMALIZATION GROUP APPROACH FOR AN ELECTRON-PHONON INTERACTION

A finite chain calculation in terms of Hubbard X-operators is explored by setting up a vibronic Harniltonian. The model conveniently transformed into a form so that in the case of strong coupling a numerical renormalization group approach is applicable. To test the technique, a one particle Green function is calculated for the model Harniltonian

Functional renormalization group at large N for disordered systems.

We introduce a method, based on an exact calculation of the effective action at large N, to bridge the gap between mean-field theory and renormalization in complex systems. We apply it to a d-dimensional manifold in a random potential for large embedding space dimension N. This yields a functional renormalization group equation valid for any d, which contains both the O(epsilon=4-d) results of ...

Cluster Functional Renormalization Group

Functional renormalization group (FRG) has become a diverse and powerful tool to derive effective low-energy scattering vertices of interacting many-body systems. Starting from a non-interacting expansion point of the action, the flow of the RG parameter Λ allows to trace the evolution of the effective one-particle and two-particle vertices towards low energies by taking into account the vertex...

a numerical renormalization group approach for an electron-phonon interaction

a finite chain calculation in terms of hubbard x-operators is explored by setting up a vibronic harniltonian. the model conveniently transformed into a form so that in the case of strong coupling a numerical renormalization group approach is applicable. to test the technique, a one particle green function is calculated for the model harniltonian

Renormalization Group Renormalization Group