Momentum Dependent Local-Ansatz with Hybrid Wavefunction from Weak to Strong Electron Correlations

Abstract

The variational theory of momentum dependent local-ansatz (MLA) has been generalized by introducing a hybrid (HB) wavefunction as a starting wavefunction, whose potential can flexibly change from the Hartree-Fock type to the alloy-analogy type by varying a weighting factor from zero to one. Numerical results based on the half-filled band Hubbard model on the hypercubic lattice in infinite dimensions show up that the new wavefunction yields the ground-state energy lower than that of the Gutzwiller wavefunction (GW) in the whole Coulomb interaction regime. Calculated double occupation number is smaller than the result of the GW in the weak Coulomb interaction regime, and remains finite in the strong regime. Furthermore, the momentum distribution shows a distinct momentum dependence, which is qualitatively different from that of the GW.

24 pages, 5 figures

References in corpus (7)

• Variational Monte Carlo Method Combined with Quantum-Number Projection and Multi-Variable Optimization
• Gutzwiller theory of band magnetism in LaOFeAs
• Magnetic Properties of Ab initio Model for Iron-Based Superconductors LaFeAsO
• Approximate solution of variational wave functions for strongly correlated systems: Description of bound excitons in metals and insulators
• Local-Ansatz Approach with Momentum Dependent Variational Parameters to Correlated Electron Systems
• Momentum Dependent Local-Ansatz Approach to Correlated Electron Systems: Non Half-Filled Case
• Momentum Dependent Local-Ansatz Wavefunction from Weak to Strong Electron Correlations

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• First-Principles Momentum Dependent Local Ansatz Approach to the Ground-State Properties of Iron-Group Transition Metals
• Variational Monte Carlo method for the Baeriswyl wavefunction: application to the one-dimensional bosonic Hubbard model
• Correlated Electrons and Mass Enhancement on the Beta-Mn Type Lattice
• Momentum-Dependent Local Ansatz Approach to the Metallic Ferromagnetism