Cellular Dynamical Mean Field Theory of the Periodic Anderson Model

TL;DR

This paper develops a cluster dynamical mean field theory for the three-dimensional periodic Anderson model, revealing a phase transition characterized by effective mass enhancement, Fermi surface changes, and an orbitally selective Mott transition related to the Kondo quantum critical point.

Contribution

It introduces a cluster DMFT approach to the periodic Anderson model, capturing nonlocal correlations and the nature of the phase transition beyond single-site theories.

Findings

The transition involves a large effective mass increase and Fermi surface reconstruction.

The transition is associated with an orbitally selective Mott transition of f electrons.

Significant spectral weight transfer occurs near the Fermi level during the transition.

Abstract

We develop a cluster dynamical mean field theory of the periodic Anderson model in three dimensions, taking a cluster of two sites as a basic reference frame. The mean field theory displays the basic features of the Doniach phase diagram: a paramagnetic Fermi liquid state, an antiferromagnetic state and a transition between them. In contrast with spin density wave theories, the transition is accompanied by a large increase of the effective mass everywhere on the Fermi surface and a substantial change of the Fermi surface shape across the transition. To understand the nature and the origin of the phases near the transition, we investigate the paramagnetic solution underlying the antiferromagnetic state, and identify the transition as a point where the $f$ electrons decouple from the conduction electrons undergoing an orbitally selective Mott transition. This point turns out to be intimately related to the two impurity Kondo model quantum critical point. In this regime, non local correlations become important and result in significant changes in the photoemission spectra and the de Haas-van Alphen frequencies. The transition involves considerable $f$ spectral weight transfer from the Fermi level to its immediate vicinity, rather than to the Hubbard bands as in single site DMFT.