Dynamical Mean Field Theory, Density-Matrix Embedding Theory and Rotationally Invariant Slave Bosons: a Unified Perspective

TL;DR

This paper unifies DMFT, DMET, and RISB methods, showing their relationships and enabling transfer of extensions like temperature dependence among them for improved theoretical modeling.

Contribution

It provides a unified framework connecting DMFT, DMET, and RISB, revealing their relationships and facilitating method extensions.

Findings

DMET is a simplified RISB with quasiparticle weight set to one

Extensions of one method can be transferred to others, e.g., temperature dependence

A temperature-dependent free-energy formula for DMET derived from RISB

Abstract

We present a unified perspective on Dynamical Mean Field Theory (DMFT), Density-Matrix Embedding Theory (DMET) and Rotationally Invariant Slave Bosons (RISB). We show that DMET can be regarded as a simplification of the RISB method where the quasiparticle weight is set to unity. This relation allows to easily transpose extensions of a given method to another: for instance, a temperature-dependent version of RISB can be used to derive a temperature-dependent free-energy formula for DMET.