Non-local Correlation Effects in Fermionic Many-Body Systems: Overcoming the Non-causality Problem

Abstract

Motivated by the intriguing physics of quasi-2d fermionic systems, such as high-temperature superconducting oxides, layered transition metal chalcogenides or surface or interface systems, the development of many-body computational methods geared at including both local and non-local electronic correlations has become a rapidly evolving field. It has been realized, however, that the success of such methods can be hampered by the emergence of noncausal features in the effective or observable quantities involved. Here, we present a new approach of extending local many-body techniques such as dynamical mean field theory (DMFT) to nonlocal correlations, which preserves causality and has a physically intuitive interpretation. Our strategy has implications for the general class of DMFT-inspired many-body methods, and can be adapted to cluster, dual boson or dual fermion techniques with minimal effort.

6 pages + 5 pages supplemental material

References in corpus (25)

• Coherence-incoherence crossover in the normal state of iron-oxypnictides and importance of the Hund's rule coupling
• Dynamical vertex approximation - a step beyond dynamical mean field theory
• Dynamical Mean-Field Theory within an Augmented Plane-Wave Framework: Assessing Electronic Correlations in the Iron Pnictide LaFeAsO
• Cluster Dynamical Mean Field Theory of the Mott Transition
• Orbital-Selective Mott transition out of band degeneracy lifting
• Screening and Non-local Correlations in the Extended Hubbard Model from Self-Consistent Combined GW and Dynamical Mean Field Theory
• Dichotomy between large local and small ordered magnetic moment in Iron-based superconductors
• Combined GW and dynamical mean field theory: Dynamical screening effects in transition metal oxides
• Spectral Properties of Correlated Materials: Local Vertex and Non-Local Two-Particle Correlations from Combined GW and Dynamical Mean Field Theory
• Ab initio dynamical vertex approximation
• Systematically improvable multi-scale solver for correlated electron systems
• Multitier self-consistent $GW$+EDMFT
• Pseudogap and Mott Transition Studied by Cellular Dynamical Mean Field Theory
• Extended dynamical mean-field study of the Hubbard model with long range interactions
• Finite temperature quantum embedding theories for correlated systems
• On the dangers of partial diagrammatic summations: Benchmarks for the two-dimensional Hubbard model in the weak-coupling regime
• Dynamical Screening Effects in Correlated Electron Materials -- A Progress Report on Combined Many-Body Perturbation and Dynamical Mean Field Theory: "GW+DMFT"
• Dynamical mean-field theory and numerical renormalization group study of superconductivity in the attractive Hubbard model
• Conservation in two-particle self-consistent extensions of dynamical-mean-field-theory
• Self-consistent ladder D$\Gamma$A approach
• Screening from $e_g$ states and antiferromagnetic correlations in $d^{(1,2,3)}$ perovskites: A $GW$+EDMFT investigation
• Spectral functions of Sr${}_2$IrO${}_4$: theory versus experiment
• Causal versus local $GW$+EDMFT scheme and application to the triangular-lattice extended Hubbard model
• Causal optimization method for imaginary-time Green's functions in interacting electron systems
• Non-local Coulomb interactions on the triangular lattice in the high-doping regime: Spectra and charge dynamics from Extended Dynamical Mean Field Theory

Cited by in corpus (6)

• Photo-induced nonequilibrium states in Mott insulators
• Strongly correlated superconductivity with long-range spatial fluctuations
• Improved effective vertices in the multi-orbital Two-Particle Self-Consistent method from Dynamical Mean-Field Theory
• Fully {\it ab-initio} electronic structure of Ca${}_2$RuO${}_4$
• Measuring the ultrafast screening of $U$ in photo-excited charge-transfer insulators with time-resolved X-ray absorption spectroscopy
• Dual-space cluster-diagrammatic approach to nonlocal electronic correlations