Improvement of the simplification method for the local two-particle full-vertex towards precise frequency behavior
arXiv:2505.19596 · doi:10.1103/PhysRevB.111.205136
Abstract
Estimating the local two-particle vertex functions, which are crucial for capturing the spatial fluctuation of the effective field beyond the single-site DMFT, is still challenging. In our previous work, we developed a computationally efficient method for estimating the local full-vertex in DMFT, where we can obtain the local two-particle full-vertex from the one-particle self-energy. In this study, we further enhance our method by refining its formulation to be more faithful to the diagrammatic structure of the full-vertex. With this improvement, we can qualitatively reproduce the characteristic frequency structures of the full-vertex obtained by the numerically exact methods. In particular, the improved version of the simplified full-vertex captures a sharp value change in the cross structure.
14 pages, 10 figures, 1 table
References in corpus (14)
- Hybridization expansion impurity solver: General formulation and application to Kondo lattice and two-orbital models
- Dynamical vertex approximation - a step beyond dynamical mean field theory
- Dual fermion approach to the two-dimensional Hubbard model: Antiferromagnetic fluctuations and Fermi arcs
- Truncated Configuration Interaction expansions as solvers for correlated quantum impurity models and dynamical mean field theory
- Influence of Spatial Correlations in Strongly Correlated Electron Systems: Extension to Dynamical Mean Field Approximation
- Superconductivity, antiferromagnetism and phase separation in the two-dimensional Hubbard model: A dual-fermion approach
- Sub-matrix updates for the Continuous-Time Auxiliary Field algorithm
- Continuous-Time Quantum Monte Carlo Method for the Coqblin-Schrieffer Model
- Worm Improved Estimators in Continuous-time Quantum Monte Carlo
- Analytic impurity solver with the Kondo strong-coupling asymptotics
- Real-frequency quantum field theory applied to the single-impurity Anderson model
- Multi-orbital simplified parquet equations for strongly correlated electrons
- Compressing the two-particle Green's function using wavelets: Theory and application to the Hubbard atom
- Simplification of the local full vertex in the impurity problem in DMFT and its applications for the nonlocal correlation