Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2007-09-28
Phys. Rev. B 77, 045133 (2008)
Physics
Condensed Matter
Strongly Correlated Electrons
19 pages, 19 figures, v3 with minor corrections, extended discussion
Scientific paper
10.1103/PhysRevB.77.045133
The variational cluster approach (VCA) is applied to the one-dimensional Hubbard model at zero temperature using clusters (chains) of up to ten sites with full diagonalization and the Lanczos method as cluster solver. Within the framework of the self-energy-functional theory (SFT), different cluster reference systems with and without bath degrees of freedom, in different topologies and with different sets of variational parameters are considered. Static and one-particle dynamical quantities are calculated for half-filling as a function of U as well as for fixed U as a function of the chemical potential to study the interaction- and filling-dependent metal-insulator (Mott) transition. The recently developed Q-matrix technique is used to compute the SFT grand potential. For benchmarking purposes we compare the VCA results with exact results available from the Bethe ansatz, with essentially exact dynamical DMRG data, with (cellular) dynamical mean-field theory and full diagonalization of isolated Hubbard chains. Several issues are discussed including convergence of the results with cluster size, the ability of cluster approaches to access the critical regime of the Mott transition, efficiency in the optimization of correlated-site vs. bath-site parameters and of multi-dimensional parameter optimization. We also study the role of bath sites for the description of excitation properties and as charge reservoirs for the description of filling dependencies. The VCA turns out to be a computationally cheap method which is competitive with established cluster approaches.
Balzer Matthias
Hanke Werner
Potthoff Michael
No associations
LandOfFree
Mott transition in one dimension: Benchmarking dynamical cluster approaches does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Mott transition in one dimension: Benchmarking dynamical cluster approaches, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mott transition in one dimension: Benchmarking dynamical cluster approaches will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-715150